diff --git a/src/main/java/nextstep/courses/domain/Capacity.java b/src/main/java/nextstep/courses/domain/Capacity.java
new file mode 100644
index 0000000000..8153d51d63
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/Capacity.java
@@ -0,0 +1,18 @@
+package nextstep.courses.domain;
+
+public class Capacity {
+
+    private int max;
+    private int current;
+
+    public Capacity(int max, int current) {
+        this.max = max;
+        this.current = current;
+    }
+
+    public void validateAvailable() {
+        if (current > max) {
+            throw new IllegalStateException();
+        }
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/CoverImage.java b/src/main/java/nextstep/courses/domain/CoverImage.java
new file mode 100644
index 0000000000..6c677c07e7
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/CoverImage.java
@@ -0,0 +1,17 @@
+package nextstep.courses.domain;
+
+public class CoverImage {
+    private ImageSize imageSize;
+    private ImageType imageType;
+    private ImageDimension imageDimension;
+
+    public CoverImage(int size, ImageType imageType, int width, int height) {
+        this(new ImageSize(size), imageType, new ImageDimension(width, height));
+    }
+
+    public CoverImage(ImageSize imageSize, ImageType imageType, ImageDimension imageDimension) {
+        this.imageSize = imageSize;
+        this.imageType = imageType;
+        this.imageDimension = imageDimension;
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/EnrollmentPolicy.java b/src/main/java/nextstep/courses/domain/EnrollmentPolicy.java
new file mode 100644
index 0000000000..ee8b0773e7
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/EnrollmentPolicy.java
@@ -0,0 +1,7 @@
+package nextstep.courses.domain;
+
+import nextstep.payments.domain.Payment;
+
+public interface EnrollmentPolicy {
+    void validateEnrollment(Payment payment);
+}
diff --git a/src/main/java/nextstep/courses/domain/FreeEnrollmentPolicy.java b/src/main/java/nextstep/courses/domain/FreeEnrollmentPolicy.java
new file mode 100644
index 0000000000..21720b9ec7
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/FreeEnrollmentPolicy.java
@@ -0,0 +1,10 @@
+package nextstep.courses.domain;
+
+import nextstep.payments.domain.Payment;
+
+public class FreeEnrollmentPolicy implements EnrollmentPolicy{
+    @Override
+    public void validateEnrollment(Payment payment) {
+        // 무료강의는 검증하지 않는다
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/ImageDimension.java b/src/main/java/nextstep/courses/domain/ImageDimension.java
new file mode 100644
index 0000000000..806de0874b
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/ImageDimension.java
@@ -0,0 +1,30 @@
+package nextstep.courses.domain;
+
+public class ImageDimension {
+
+    public static final int HEIGHT_RATIO = 2;
+    public static final int WIDTH_RATIO = 3;
+    public static final int MIN_WIDTH = 300;
+    public static final int MIN_HEIGHT = 200;
+    private int width;
+    private int height;
+
+    public ImageDimension(int width, int height) {
+        validateMinimumSize(width, height);
+        validateRatio(width, height);
+        this.width = width;
+        this.height = height;
+    }
+
+    private static void validateMinimumSize(int width, int height) {
+        if (width < MIN_WIDTH || height < MIN_HEIGHT) {
+            throw new IllegalArgumentException();
+        }
+    }
+
+    private static void validateRatio(int width, int height) {
+        if (!(HEIGHT_RATIO * width == WIDTH_RATIO * height)) {
+            throw new IllegalArgumentException();
+        }
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/ImageSize.java b/src/main/java/nextstep/courses/domain/ImageSize.java
new file mode 100644
index 0000000000..b03838043b
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/ImageSize.java
@@ -0,0 +1,29 @@
+package nextstep.courses.domain;
+
+import java.util.Objects;
+
+public class ImageSize {
+
+    public static final int MAX_SIZE = 1_048_576;
+    private int imageSize;
+
+    public ImageSize(int imageSize) {
+        if (imageSize > MAX_SIZE) {
+            throw new IllegalArgumentException();
+        }
+        this.imageSize = imageSize;
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (this == object) return true;
+        if (object == null || getClass() != object.getClass()) return false;
+        ImageSize imageSize1 = (ImageSize) object;
+        return imageSize == imageSize1.imageSize;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(imageSize);
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/ImageType.java b/src/main/java/nextstep/courses/domain/ImageType.java
new file mode 100644
index 0000000000..a8420c326e
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/ImageType.java
@@ -0,0 +1,30 @@
+package nextstep.courses.domain;
+
+import java.util.Arrays;
+
+public enum ImageType {
+
+    GIF("gif"),
+    JPG("jpg", "jpeg"),
+    PNG("png"),
+    SVG("svg");
+
+    private final String[] extensions;
+
+    ImageType(String... extensions) {
+        this.extensions = extensions;
+    }
+
+    private boolean matches(String extension) {
+        return Arrays.stream(extensions)
+                .anyMatch(ext -> ext.equalsIgnoreCase(extension));
+    }
+
+    public static ImageType from(String extension) {
+        return Arrays.stream(values())
+                .filter(type -> type.matches(extension))
+                .findFirst()
+                .orElseThrow(() -> new IllegalArgumentException());
+    }
+
+}
diff --git a/src/main/java/nextstep/courses/domain/Money.java b/src/main/java/nextstep/courses/domain/Money.java
new file mode 100644
index 0000000000..bd571b378f
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/Money.java
@@ -0,0 +1,28 @@
+package nextstep.courses.domain;
+
+import java.util.Objects;
+
+public class Money {
+    private final long amount;
+
+    public Money(long amount) {
+        this.amount = amount;
+    }
+
+    public boolean isEqualTo(Money other) {
+        return this.equals(other);
+    }
+
+    @Override
+    public boolean equals(Object object) {
+        if (this == object) return true;
+        if (object == null || getClass() != object.getClass()) return false;
+        Money money = (Money) object;
+        return amount == money.amount;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hashCode(amount);
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/PaidEnrollmentPolicy.java b/src/main/java/nextstep/courses/domain/PaidEnrollmentPolicy.java
new file mode 100644
index 0000000000..f471b5a3fd
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/PaidEnrollmentPolicy.java
@@ -0,0 +1,26 @@
+package nextstep.courses.domain;
+
+import nextstep.payments.domain.Payment;
+
+public class PaidEnrollmentPolicy implements EnrollmentPolicy {
+
+    private final Money money;
+    private final Capacity capacity;
+
+    public PaidEnrollmentPolicy(Money money, Capacity capacity) {
+        this.money = money;
+        this.capacity = capacity;
+    }
+
+    @Override
+    public void validateEnrollment(Payment payment) {
+        capacity.validateAvailable();
+        validatePayment(payment);
+    }
+
+    private void validatePayment(Payment payment) {
+        if (!payment.isSameAmount(money)) {
+            throw new IllegalArgumentException();
+        }
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/Session.java b/src/main/java/nextstep/courses/domain/Session.java
new file mode 100644
index 0000000000..584e59ec69
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/Session.java
@@ -0,0 +1,38 @@
+package nextstep.courses.domain;
+
+import nextstep.payments.domain.Payment;
+
+import java.time.LocalDateTime;
+
+public class Session {
+    private final long id;
+    private final SessionDuration sessionDuration;
+    private final CoverImage coverImage;
+    private final EnrollmentPolicy enrollmentPolicy;
+    private final SessionState sessionState;
+
+    public Session(long id
+            , LocalDateTime startDate
+            , LocalDateTime endDate
+            , int size
+            , ImageType imageType
+            , int width
+            , int height
+            , EnrollmentPolicy enrollmentPolicy
+            , SessionState sessionState) {
+        this(id, new SessionDuration(startDate, endDate), new CoverImage(size, imageType, width, height)
+                , enrollmentPolicy, sessionState);
+    }
+
+    public Session(long id, SessionDuration sessionDuration, CoverImage coverImage
+            , EnrollmentPolicy enrollmentPolicy, SessionState sessionState) {
+        this.id = id;
+        this.sessionDuration = sessionDuration;
+        this.coverImage = coverImage;
+        this.enrollmentPolicy = enrollmentPolicy;
+        this.sessionState = sessionState;
+    }
+
+    public void enroll() {
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/SessionDuration.java b/src/main/java/nextstep/courses/domain/SessionDuration.java
new file mode 100644
index 0000000000..54d7714a2c
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/SessionDuration.java
@@ -0,0 +1,20 @@
+package nextstep.courses.domain;
+
+import java.time.LocalDateTime;
+
+public class SessionDuration {
+    private LocalDateTime startDate;
+    private LocalDateTime endDate;
+
+    public SessionDuration(LocalDateTime startDate, LocalDateTime endDate) {
+        validateDate(startDate, endDate);
+        this.startDate = startDate;
+        this.endDate = endDate;
+    }
+
+    private void validateDate(LocalDateTime startDate, LocalDateTime endDate) {
+        if (!startDate.isBefore(endDate)) {
+            throw new IllegalArgumentException();
+        }
+    }
+}
diff --git a/src/main/java/nextstep/courses/domain/SessionState.java b/src/main/java/nextstep/courses/domain/SessionState.java
new file mode 100644
index 0000000000..e087309d58
--- /dev/null
+++ b/src/main/java/nextstep/courses/domain/SessionState.java
@@ -0,0 +1,13 @@
+package nextstep.courses.domain;
+
+public enum SessionState {
+    READY,
+    OPEN,
+    CLOSED;
+
+    public void validateEnroll() {
+        if (this != OPEN) {
+            throw new IllegalStateException();
+        }
+    }
+}
diff --git a/src/main/java/nextstep/payments/domain/Payment.java b/src/main/java/nextstep/payments/domain/Payment.java
index 57d833f851..6d4c2b720c 100644
--- a/src/main/java/nextstep/payments/domain/Payment.java
+++ b/src/main/java/nextstep/payments/domain/Payment.java
@@ -1,5 +1,7 @@
 package nextstep.payments.domain;
 
+import nextstep.courses.domain.Money;
+
 import java.time.LocalDateTime;
 
 public class Payment {
@@ -12,7 +14,7 @@ public class Payment {
     private Long nsUserId;
 
     // 결제 금액
-    private Long amount;
+    private Money amount;
 
     private LocalDateTime createdAt;
 
@@ -23,7 +25,11 @@ public Payment(String id, Long sessionId, Long nsUserId, Long amount) {
         this.id = id;
         this.sessionId = sessionId;
         this.nsUserId = nsUserId;
-        this.amount = amount;
+        this.amount = new Money(amount);
         this.createdAt = LocalDateTime.now();
     }
+
+    public boolean isSameAmount(Money money) {
+        return amount.isEqualTo(money);
+    }
 }
diff --git a/src/test/java/nextstep/courses/domain/CapacityTest.java b/src/test/java/nextstep/courses/domain/CapacityTest.java
new file mode 100644
index 0000000000..38d3806c08
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/CapacityTest.java
@@ -0,0 +1,17 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class CapacityTest {
+
+    @Test
+    @DisplayName("최대 인원을 넘어서 수강신청이 들어오면 Exceptionn")
+    void max() {
+        Capacity capacity = new Capacity(300, 301);
+        assertThatThrownBy(() -> capacity.validateAvailable())
+                .isInstanceOf(IllegalStateException.class);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/ImageDimensionTest.java b/src/test/java/nextstep/courses/domain/ImageDimensionTest.java
new file mode 100644
index 0000000000..1f3805d39a
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/ImageDimensionTest.java
@@ -0,0 +1,41 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatNoException;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class ImageDimensionTest {
+
+    @Test
+    @DisplayName("width가 300px 미만이면 예외가 발생한다")
+    void create_width_exception() {
+        assertThatThrownBy(() -> new ImageDimension(299, 200))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+
+    @Test
+    @DisplayName("height가 200px 미만이면 예외가 발생한다")
+    void create_height_exception() {
+        assertThatThrownBy(() -> new ImageDimension(300, 199))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+
+    @Test
+    @DisplayName("width와 height는 3:2 비율이 아니면 예외가 발생한다")
+    void create_width_height_exception() {
+        assertThatThrownBy(() -> new ImageDimension(300, 300))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+
+    @Test
+    @DisplayName("width_height_정상생성")
+    void create_success() {
+        assertThatNoException()
+                .isThrownBy(() -> new ImageDimension(300, 200));
+
+        assertThatNoException()
+                .isThrownBy(() -> new ImageDimension(600, 400));
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/ImageSizeTest.java b/src/test/java/nextstep/courses/domain/ImageSizeTest.java
new file mode 100644
index 0000000000..5685a14cdc
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/ImageSizeTest.java
@@ -0,0 +1,30 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static nextstep.courses.domain.ImageSize.MAX_SIZE;
+import static org.assertj.core.api.Assertions.*;
+
+class ImageSizeTest {
+
+    @Test
+    @DisplayName("1MB 이하의 이미지 크기는 생성된다")
+    void create_image_size() {
+        // 방법1
+        ImageSize imageSize = new ImageSize(MAX_SIZE);
+
+        assertThat(imageSize).isEqualTo(new ImageSize(MAX_SIZE));
+
+        // 방법2
+        assertThatNoException()
+                .isThrownBy(() -> new ImageSize(MAX_SIZE));
+    }
+
+    @Test
+    @DisplayName("1MB보다 큰 이미지 크기는 예외가 발생한다")
+    void create_image_size_max_exception() {
+        assertThatThrownBy(() -> new ImageSize(MAX_SIZE + 1))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/ImageTypeTest.java b/src/test/java/nextstep/courses/domain/ImageTypeTest.java
new file mode 100644
index 0000000000..080d0384e7
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/ImageTypeTest.java
@@ -0,0 +1,28 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class ImageTypeTest {
+
+    @Test
+    @DisplayName("유효한 확장자")
+    void from_valid_extension() {
+        assertThat(ImageType.from("gif")).isEqualTo(ImageType.GIF);
+        assertThat(ImageType.from("GIF")).isEqualTo(ImageType.GIF);
+        assertThat(ImageType.from("jpg")).isEqualTo(ImageType.JPG);
+        assertThat(ImageType.from("jpeg")).isEqualTo(ImageType.JPG);
+    }
+
+    @Test
+    @DisplayName("유효하지 않은 확장자")
+    void from_invalid_extension() {
+        assertThatThrownBy(() -> ImageType.from("txt"))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+
+
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/MoneyTest.java b/src/test/java/nextstep/courses/domain/MoneyTest.java
new file mode 100644
index 0000000000..361ef9858a
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/MoneyTest.java
@@ -0,0 +1,17 @@
+package nextstep.courses.domain;
+
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.*;
+
+class MoneyTest {
+
+    @Test
+    @DisplayName("금액이 같으면, true")
+    void isEqualTo() {
+        Money money = new Money(5000);
+        assertThat(money.isEqualTo(new Money(5000))).isTrue();
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/SessionDurationTest.java b/src/test/java/nextstep/courses/domain/SessionDurationTest.java
new file mode 100644
index 0000000000..fbc26915fe
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/SessionDurationTest.java
@@ -0,0 +1,31 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import java.time.LocalDateTime;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class SessionDurationTest {
+
+    @Test
+    @DisplayName("시작일과 종료일이 같으면 exception")
+    void start_equals_end_exception() {
+        LocalDateTime start = LocalDateTime.of(2025, 12, 15, 00, 00);
+        LocalDateTime end = LocalDateTime.of(2025, 12, 15, 00, 00);
+
+        assertThatThrownBy(() -> new SessionDuration(start, end))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+
+    @Test
+    @DisplayName("시작일이 종료일보다 크면 exception")
+    void start_after_end_exception() {
+        LocalDateTime start = LocalDateTime.of(2025, 12, 15, 14, 00);
+        LocalDateTime end = LocalDateTime.of(2025, 12, 15, 13, 00);
+
+        assertThatThrownBy(() -> new SessionDuration(start, end))
+                .isInstanceOf(IllegalArgumentException.class);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/SessionStateTest.java b/src/test/java/nextstep/courses/domain/SessionStateTest.java
new file mode 100644
index 0000000000..85ac02fc3b
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/SessionStateTest.java
@@ -0,0 +1,26 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatCode;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+class SessionStateTest {
+    @Test
+    @DisplayName("OPEN은 등록이 가능하다")
+    void enroll_success() {
+        assertThatCode(() -> SessionState.OPEN.validateEnroll())
+                .doesNotThrowAnyException();
+    }
+
+    @Test
+    @DisplayName("READY나 CLOSED는 등록할 수 없다")
+    void enroll_fail() {
+        assertThatThrownBy(() -> SessionState.READY.validateEnroll())
+                .isInstanceOf(IllegalStateException.class);
+
+        assertThatThrownBy(() -> SessionState.CLOSED.validateEnroll())
+                .isInstanceOf(IllegalStateException.class);
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/nextstep/courses/domain/SessionTest.java b/src/test/java/nextstep/courses/domain/SessionTest.java
new file mode 100644
index 0000000000..a14c62e3d9
--- /dev/null
+++ b/src/test/java/nextstep/courses/domain/SessionTest.java
@@ -0,0 +1,13 @@
+package nextstep.courses.domain;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class SessionTest {
+
+    @Test
+    void enroll() {
+
+    }
+}
\ No newline at end of file