diff --git a/package.json b/package.json
index ddfe02d89..1f3c56fc6 100644
--- a/package.json
+++ b/package.json
@@ -53,6 +53,8 @@
     "mocha": "^2.3.4",
     "rollup": "^0.25.4",
     "rollup-plugin-babel": "^2.4.0",
+    "sinon": "^1.17.3",
+    "sinon-chai": "^2.8.0",
     "todomvc-app-css": "^2.0.3",
     "uglify-js": "^2.6.2",
     "vue": "^1.0.17",
diff --git a/src/override.js b/src/override.js
index 470146b83..fd408f8a5 100644
--- a/src/override.js
+++ b/src/override.js
@@ -51,7 +51,7 @@ export default function (Vue) {
       if (actions) {
         options.methods = options.methods || {}
         for (let key in actions) {
-          options.methods[key] = makeBoundAction(this.$store, actions[key])
+          options.methods[key] = makeBoundAction(this.$store, actions[key], key)
         }
       }
     }
@@ -126,9 +126,13 @@ export default function (Vue) {
    *
    * @param {Store} store
    * @param {Function} action
+   * @param {String} key
    */
 
-  function makeBoundAction (store, action) {
+  function makeBoundAction (store, action, key) {
+    if (typeof action !== 'function') {
+      console.warn(`[vuex] Action bound to key 'vuex.actions.${key}' is not a function.`)
+    }
     return function vuexBoundAction (...args) {
       return action.call(this, store, ...args)
     }
diff --git a/test/unit/test.js b/test/unit/test.js
index e5132e401..77d9e7cf8 100644
--- a/test/unit/test.js
+++ b/test/unit/test.js
@@ -1,9 +1,12 @@
-import { expect } from 'chai'
+import chai, { expect } from 'chai'
+import sinonChai from 'sinon-chai'
+import sinon from 'sinon'
 import Vue from 'vue'
 import Vuex from '../../src'
 import * as util from '../../src/util'
 
 Vue.use(Vuex)
+chai.use(sinonChai)
 
 const TEST = 'TEST'
 
@@ -404,4 +407,19 @@ describe('Vuex', () => {
     })
     expect(store.state.a).to.equal(3)
   })
+
+  it('console.warn when action is not a function', function () {
+    sinon.spy(console, 'warn')
+
+    new Vue({
+      vuex: {
+        actions: {
+          test: undefined
+        }
+      }
+    })
+
+    expect(console.warn).to.have.been.calledWith('[vuex] Action bound to key \'vuex.actions.test\' is not a function.')
+    console.warn.restore()
+  })
 })