diff --git a/README.md b/README.md
index 387ec5a..4ecb031 100644
--- a/README.md
+++ b/README.md
@@ -1,10 +1,21 @@
-# OpenCV_Android_SDK
- 
-## Download sourcecode:
+## OpenCV_Android_SDK
 
-./build.sh download or ./build.sh download [version]
+### Setup Enviroment:
 
-## Build:
+This setup to build OpenCV Android SDK for Android 9 (28) and Android 10 (30) and build on Ubuntu 18.
+- sdk cmdline-tools path: /mnt/d/Android-SDK/cmdline-tools/bin
+- SDK path: `/mnt/d/Android-SDK/Linux`
+- NDK path: `/mnt/d/Android-SDK/Linux/ndk/21.4.7075529`
 
-./build.sh or ./build.sh [version]
+1. Install JDK: `sudo apt install default-jdk`
+2. Install [sdk cmdline-tools](https://developer.android.com/studio#command-tools "sdk cmdline-tools") and add sdk cmdline-tools path to `.bashrc`
+3. Download SDK, NDK, CMake: `sdkmanager "platform-tools" "platforms;android-28" "platforms;android-30" "ndk;21.4.7075529" "cmake;3.10.2.4988404" "build-tools;28.0.3" "build-tools;30.0.3" --sdk_root=/mnt/d/Android-SDK/Linux`
+
+### Download OpenCV sourcecode:
+
+`./build.sh download` or `./build.sh download [version]`
+
+### Build OpenCV Android SDK:
+edit config file: config.sh
+then run `./build.sh` or `./build.sh [version]`