diff --git a/merkle/package.json b/merkle/package.json
index c958835..e8259a3 100644
--- a/merkle/package.json
+++ b/merkle/package.json
@@ -26,7 +26,7 @@
     "truffle-assertions": "^0.9.2"
   },
   "dependencies": {
-    "@openzeppelin/contracts": "^3.1.0",
+    "@openzeppelin/contracts": "^4.4.2",
     "@truffle/hdwallet-provider": "^1.0.29",
     "bn.js": "^4.11.0",
     "ethereumjs-util": "^7.0.4",
diff --git a/merkle/yarn.lock b/merkle/yarn.lock
index 7145882..38d28cb 100644
--- a/merkle/yarn.lock
+++ b/merkle/yarn.lock
@@ -232,10 +232,10 @@
     fs-extra "^8.1.0"
     try-require "^1.2.1"
 
-"@openzeppelin/contracts@^3.1.0":
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/@openzeppelin/contracts/-/contracts-3.1.0.tgz#bcea457ef89069fbe5a617f50b25b6a8272895d5"
-  integrity sha512-dVXDnUKxrAKLzPdCRkz+N8qsVkK1XxJ6kk3zuI6zaQmcKxN7CkizoDP7lXxcs/Mi2I0mxceTRjJBqlzFffLJrQ==
+"@openzeppelin/contracts@^4.4.2":
+  version "4.4.2"
+  resolved "https://registry.yarnpkg.com/@openzeppelin/contracts/-/contracts-4.4.2.tgz#4e889c9c66e736f7de189a53f8ba5b8d789425c2"
+  integrity sha512-NyJV7sJgoGYqbtNUWgzzOGW4T6rR19FmX1IJgXGdapGPWsuMelGJn9h03nos0iqfforCbCB0iYIR0MtIuIFLLw==
 
 "@openzeppelin/test-helpers@^0.5.6":
   version "0.5.6"