diff --git a/contracts/RewardToken.sol b/contracts/RewardToken.sol
index a25f798..63a062a 100644
--- a/contracts/RewardToken.sol
+++ b/contracts/RewardToken.sol
@@ -13,7 +13,7 @@ contract RewardToken is ERC20, ERC20Burnable, AccessControl {
         _grantRole(MINTER_ROLE, msg.sender);
     }
 
-    function mint(address to, uint256 amount) public{
+    function mint(address to, uint256 amount) public onlyRole(MINTER_ROLE) {
         _mint(to, amount);
     }
 }