diff --git a/packages/mcp-server/package-lock.json b/packages/mcp-server/package-lock.json
index 217beb9..d8f4f1e 100644
--- a/packages/mcp-server/package-lock.json
+++ b/packages/mcp-server/package-lock.json
@@ -12,7 +12,7 @@
                 "@modelcontextprotocol/sdk": "^1.0.4",
                 "linkedom": "^0.18.0",
                 "open": "^10.1.0",
-                "zod": "^3.24.0"
+                "zod": "^4.0.0"
             },
             "bin": {
                 "next-ai-drawio-mcp": "dist/index.js"
@@ -2024,9 +2024,9 @@
             }
         },
         "node_modules/zod": {
-            "version": "3.25.76",
-            "resolved": "https://registry.npmjs.org/zod/-/zod-3.25.76.tgz",
-            "integrity": "sha512-gzUt/qt81nXsFGKIFcC3YnfEAx5NkunCfnDlvuBSSFS02bcXu4Lmea0AFIUwbLWxWPx3d9p8S5QoaujKcNQxcQ==",
+            "version": "4.2.1",
+            "resolved": "https://registry.npmjs.org/zod/-/zod-4.2.1.tgz",
+            "integrity": "sha512-0wZ1IRqGGhMP76gLqz8EyfBXKk0J2qo2+H3fi4mcUP/KtTocoX08nmIAHl1Z2kJIZbZee8KOpBCSNPRgauucjw==",
             "license": "MIT",
             "peer": true,
             "funding": {
diff --git a/packages/mcp-server/package.json b/packages/mcp-server/package.json
index 6823615..a7ab628 100644
--- a/packages/mcp-server/package.json
+++ b/packages/mcp-server/package.json
@@ -39,7 +39,7 @@
         "@modelcontextprotocol/sdk": "^1.0.4",
         "linkedom": "^0.18.0",
         "open": "^10.1.0",
-        "zod": "^3.24.0"
+        "zod": "^4.0.0"
     },
     "devDependencies": {
         "@types/node": "^20",