diff --git a/packages/sdk/helper/src/project/npm-dependency-policy.ts b/packages/sdk/helper/src/project/npm-dependency-policy.ts
index a8877826e2..727bd6648a 100644
--- a/packages/sdk/helper/src/project/npm-dependency-policy.ts
+++ b/packages/sdk/helper/src/project/npm-dependency-policy.ts
@@ -23,7 +23,7 @@ const EXTERNAL_NPM_DEPENDENCY_SPECS: Readonly<Record<string, string>> = {
   '@cordisjs/plugin-timer': '^1.1.2',
   '@types/node': '^22.20.0',
   cordis: '^4.0.0-rc.7',
-  tsdown: '^0.22.2',
+  tsdown: '0.22.2',
   tsx: '^4.22.4',
   typescript: '^6.0.3',
 }
diff --git a/packages/sdk/helper/tests/documents.spec.ts b/packages/sdk/helper/tests/documents.spec.ts
index 1ba8b9bd68..1b8050b90f 100644
--- a/packages/sdk/helper/tests/documents.spec.ts
+++ b/packages/sdk/helper/tests/documents.spec.ts
@@ -282,6 +282,7 @@ describe('package manager strategies', () => {
       section: 'devDependencies', spec: '^4.0.0-rc.7',
     })
     expect(resolveNpmDependency('@cordisjs/plugin-hmr', 'dependencies', '0.0.1').spec).toBe('^1.0.15')
+    expect(resolveNpmDependency('tsdown', 'devDependencies', '0.0.1').spec).toBe('0.22.2')
     expect(resolveNpmDependency('@deepseek-ai/dsh-tools', 'dependencies', '1.2.3').spec).toBe('^1.2.3')
     expect(() => resolveNpmDependency('unknown', 'dependencies', '0.0.1')).toThrow('no generated-project')
   })