diff --git a/icu4c/source/common/wintz.cpp b/icu4c/source/common/wintz.cpp
index a8696af39d4..14fc476040c 100644
--- a/icu4c/source/common/wintz.cpp
+++ b/icu4c/source/common/wintz.cpp
@@ -216,6 +216,8 @@ static LONG getTZKeyName(char* tzKeyName, int32_t length) {
              &cbData);
     }
 
+    RegCloseKey(hkey);
+
     return result;
 }