diff --git a/contracts/Project.sol b/contracts/Project.sol
index 1fa6748..da848bd 100644
--- a/contracts/Project.sol
+++ b/contracts/Project.sol
@@ -10,6 +10,8 @@ contract Project is IProject, OwnableUpgradeable, ERC721Upgradeable {
     event SetMinter(address indexed minter);
     event SetName(uint256 indexed projectId, string name);
     event AddMetadata(uint256 indexed projectId, string name, bytes32 key, bytes value);
+    event AddOperator(uint256 indexed projectId, address operator);
+    event RemoveOperator(uint256 indexed projectId, address operator);
 
     address public minter;
     uint256 nextProjectId;
@@ -18,6 +20,22 @@ contract Project is IProject, OwnableUpgradeable, ERC721Upgradeable {
     mapping(uint256 => string) names;
     mapping(uint256 => uint8) types;
     mapping(uint256 => mapping(bytes32 => bytes)) _metadata;
+    mapping(uint256 => mapping(address => bool)) operators;
+
+    modifier onlyMinter() {
+        require(msg.sender == minter, "not minter");
+        _;
+    }
+
+    modifier onlyProjectOwner(uint256 projectId) {
+        require(msg.sender == ownerOf(projectId), "invalid owner");
+        _;
+    }
+
+    modifier onlyProjectOperator(uint256 projectId) {
+        require(msg.sender == ownerOf(projectId) || operators[projectId][msg.sender], "invalid operator");
+        _;
+    }
 
     function initialize(string calldata _name, string calldata _symbol) public initializer {
         __Ownable_init();
@@ -26,9 +44,7 @@ contract Project is IProject, OwnableUpgradeable, ERC721Upgradeable {
     }
 
     // @deprecated
-    function mint(address _owner) external returns (uint256 projectId_) {
-        require(msg.sender == minter, "not minter");
-
+    function mint(address _owner) external onlyMinter returns (uint256 projectId_) {
         projectId_ = ++nextProjectId;
         _mint(_owner, projectId_);
     }
@@ -41,8 +57,11 @@ contract Project is IProject, OwnableUpgradeable, ERC721Upgradeable {
         return _mintProject(_owner, _name, _type);
     }
 
-    function _mintProject(address _owner, string calldata _name, uint8 _type) internal returns (uint256 projectId_) {
-        require(msg.sender == minter, "not minter");
+    function _mintProject(
+        address _owner,
+        string calldata _name,
+        uint8 _type
+    ) internal onlyMinter returns (uint256 projectId_) {
         bytes32 _nameHash = keccak256(abi.encodePacked(_name));
         require(_nameHash != EMPTY_NAME_HASH, "empty name");
         require(!nameHashes[_nameHash], "exist name");
@@ -72,15 +91,18 @@ contract Project is IProject, OwnableUpgradeable, ERC721Upgradeable {
         return _metadata[_projectId][_key];
     }
 
-    function setMetadata(uint256 _projectId, string calldata _name, bytes calldata _value) external {
-        require(msg.sender == ownerOf(_projectId), "invalid owner");
+    function setMetadata(
+        uint256 _projectId,
+        string calldata _name,
+        bytes calldata _value
+    ) external onlyProjectOperator(_projectId) {
         bytes32 _key = keccak256(abi.encodePacked(_name));
 
         _metadata[_projectId][_key] = _value;
         emit AddMetadata(_projectId, _name, _key, _value);
     }
 
-    function setName(uint256 _projectId, string calldata _name) external {
+    function setName(uint256 _projectId, string calldata _name) external onlyProjectOwner(_projectId) {
         require(msg.sender == ownerOf(_projectId), "invalid owner");
         bytes32 _nameHash = keccak256(abi.encodePacked(_name));
         require(_nameHash != EMPTY_NAME_HASH, "empty name");
@@ -95,6 +117,20 @@ contract Project is IProject, OwnableUpgradeable, ERC721Upgradeable {
         emit SetName(_projectId, _name);
     }
 
+    function addOperator(uint256 _projectId, address _operator) external onlyProjectOwner(_projectId) {
+        require(!operators[_projectId][_operator], "already operator");
+
+        operators[_projectId][_operator] = true;
+        emit AddOperator(_projectId, _operator);
+    }
+
+    function removeOperator(uint256 _projectId, address _operator) external onlyProjectOwner(_projectId) {
+        require(operators[_projectId][_operator], "not operator");
+
+        operators[_projectId][_operator] = false;
+        emit RemoveOperator(_projectId, _operator);
+    }
+
     function setMinter(address _minter) public onlyOwner {
         minter = _minter;