diff --git a/package.json b/package.json
index 0e172e5..812c82f 100644
--- a/package.json
+++ b/package.json
@@ -4,7 +4,7 @@
   "description": "HTLC Solidity implementation.",
   "main": "truffle-config.js",
   "dependencies": {
-    "@openzeppelin/contracts": "^2.4.0",
+    "@openzeppelin/contracts": "^4.7.2",
     "chai": "^4.2.0",
     "openzeppelin-test-helpers": "^0.5.1",
     "truffle-assertions": "^0.9.2"
diff --git a/yarn.lock b/yarn.lock
index 88c54db..1e771f6 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2,10 +2,10 @@
 # yarn lockfile v1
 
 
-"@openzeppelin/contracts@^2.4.0":
-  version "2.4.0"
-  resolved "https://registry.yarnpkg.com/@openzeppelin/contracts/-/contracts-2.4.0.tgz#7270f79ed1463370fe6e664d36a779aa4d3ee896"
-  integrity sha512-xeKP59REgow5TPBJh3S9BRIm7DDG+Rz3Nt4ANWGUkjk4305DHpyUD5CyMJ6nd2JMmZuFyx4mjvvlCtSJLRnN6w==
+"@openzeppelin/contracts@^4.7.2":
+  version "4.7.2"
+  resolved "https://registry.yarnpkg.com/@openzeppelin/contracts/-/contracts-4.7.2.tgz#7587416fe2d35abf574193515b8971bfe9f64bc7"
+  integrity sha512-4n/JL9izql8303mPqPdubuna/DWEMbmOzWYUWyCPhjhiEr2w3nQrjE7vZz1fBF+wzzP6dZbIcsgqACk53c9FGA==
 
 "@sindresorhus/is@^0.14.0":
   version "0.14.0"