diff --git a/src/decorator/string/IsBase64.ts b/src/decorator/string/IsBase64.ts
index c59a97009b..e7002e0e9a 100644
--- a/src/decorator/string/IsBase64.ts
+++ b/src/decorator/string/IsBase64.ts
@@ -26,7 +26,7 @@ export function IsBase64(
       name: IS_BASE64,
       constraints: [options],
       validator: {
-        validate: (value, args): boolean => isBase64(value, options),
+        validate: (value, args): boolean => isBase64(value, args?.constraints[0]),
         defaultMessage: buildMessage(eachPrefix => eachPrefix + '$property must be base64 encoded', validationOptions),
       },
     },