diff --git a/packages/plugin-eval/package.json b/packages/plugin-eval/package.json
index 1fd64c98bb..af5f5068b7 100644
--- a/packages/plugin-eval/package.json
+++ b/packages/plugin-eval/package.json
@@ -38,7 +38,8 @@
   "optionalDependencies": {
     "esbuild": "^0.11.6",
     "json5": "^2.2.0",
-    "typescript": "^4.2.3"
+    "typescript": "^4.2.3",
+    "coffeescript": "^2.5.1"
   },
   "dependencies": {
     "esbuild": "^0.11.6",
diff --git a/packages/plugin-eval/src/loaders/coffeescript.ts b/packages/plugin-eval/src/loaders/coffeescript.ts
new file mode 100644
index 0000000000..929df08ec9
--- /dev/null
+++ b/packages/plugin-eval/src/loaders/coffeescript.ts
@@ -0,0 +1,22 @@
+const { compile } = require('coffeescript')
+
+export const name = 'coffeescript'
+
+export function extractScript(expr: string) {
+  try {
+    compile(expr)
+  } catch (e) {
+    if (e.message !== 'unmatched }') throw e
+    const location = e.location
+    const sLines = expr.split('\n')
+    const row = location.first_line
+    const column = location.first_column - 1
+    return [...sLines.slice(0, row - 1), sLines[row].slice(0, column + 1)].join('\n')
+  }
+}
+
+export async function transformScript(expr: string) {
+  return compile(expr, { bare: true })
+}
+
+export const transformModule = transformScript
diff --git a/packages/plugin-eval/src/worker/loader.ts b/packages/plugin-eval/src/worker/loader.ts
index 5d3015547b..6422c32680 100644
--- a/packages/plugin-eval/src/worker/loader.ts
+++ b/packages/plugin-eval/src/worker/loader.ts
@@ -42,7 +42,7 @@ export function synthetize(identifier: string, namespace: {}, globalName?: strin
   return module
 }
 
-const extnames = new Set(['.js', '.ts', '.json', '.yml', '.yaml'])
+const extnames = new Set(['.js', '.ts', '.coffee', '.json', '.yml', '.yaml'])
 
 function* suffixes() {
   yield ''
@@ -168,6 +168,12 @@ function resolveLoader(extension: string) {
       } catch {}
     }
     throw new Error('cannot resolve loader for ".ts", you should install either esbuild or typescript + json5 by yourself')
+  } else if (extension === '.coffee') {
+    try {
+      return require('../loaders/coffeescript')
+    } catch {
+      throw new Error('cannot resolve loader for ".coffee", you should install coffeescript by yourself')
+    }
   } else {
     throw new Error(`cannot resolve loader for "${extension}", you should specify a custom loader via "config.moduleLoaders"`)
   }
diff --git a/packages/plugin-eval/tests/fixtures/addon1/foobar.coffee b/packages/plugin-eval/tests/fixtures/addon1/foobar.coffee
new file mode 100644
index 0000000000..65e774b934
--- /dev/null
+++ b/packages/plugin-eval/tests/fixtures/addon1/foobar.coffee
@@ -0,0 +1,3 @@
+import bar from './bar.yml'
+
+export default (index = 1) -> bar[index]
diff --git a/packages/plugin-eval/tests/fixtures/addon1/index.ts b/packages/plugin-eval/tests/fixtures/addon1/index.ts
index d4e3100e6a..6d506b679e 100644
--- a/packages/plugin-eval/tests/fixtures/addon1/index.ts
+++ b/packages/plugin-eval/tests/fixtures/addon1/index.ts
@@ -1,8 +1,9 @@
 import { registerCommand } from 'koishi/addons'
 import { foo } from './foo'
+import foobar from './foobar'
 
 export * from './foo'
 
 registerCommand('test', () => {
-  return foo()
+  return foo() + foobar()
 })
diff --git a/packages/plugin-eval/tests/index.spec.ts b/packages/plugin-eval/tests/index.spec.ts
index a9309e4539..14bcab2750 100644
--- a/packages/plugin-eval/tests/index.spec.ts
+++ b/packages/plugin-eval/tests/index.spec.ts
@@ -100,13 +100,20 @@ describe('Eval Loaders', () => {
     await ses.shouldReply('echo 1${"foo" as string}3', '1foo3')
     await app.stop()
   })
+
+  it('coffeescript', async () => {
+    const app = await createApp('coffeescript')
+    const ses = app.session('123')
+    await ses.shouldReply('echo 1${"foobar"}3', '1foobar3')
+    await app.stop()
+  })
 })
 
 describe('Eval Addons', () => {
   it('addon command', async () => {
     await ses.shouldReply('addon', /^addon\n扩展功能/)
     await ses.shouldReply('test -h', 'test\n测试功能')
-    await ses.shouldReply('test', 'bar')
+    await ses.shouldReply('test', 'barbaz')
   })
 
   it('sandbox injection', async () => {