diff --git a/homeassistant/core.py b/homeassistant/core.py
index 86cfec7099c..da4fd2ed102 100644
--- a/homeassistant/core.py
+++ b/homeassistant/core.py
@@ -184,6 +184,8 @@ class HomeAssistant(object):
         target: target to call.
         args: parameters for method to call.
         """
+        if target is None:
+            raise ValueError("Don't call add_job with None.")
         self.loop.call_soon_threadsafe(self.async_add_job, target, *args)
 
     @callback
diff --git a/tests/test_core.py b/tests/test_core.py
index 9221ad68352..4049d10d32d 100644
--- a/tests/test_core.py
+++ b/tests/test_core.py
@@ -6,6 +6,7 @@ from unittest.mock import patch, MagicMock
 from datetime import datetime, timedelta
 
 import pytz
+import pytest
 
 import homeassistant.core as ha
 from homeassistant.exceptions import InvalidEntityFormatError
@@ -214,6 +215,11 @@ class TestHomeAssistant(unittest.TestCase):
         assert len(self.hass._pending_tasks) == 0
         assert len(call_count) == 2
 
+    def test_add_job_with_none(self):
+        """Try to add a job with None as function."""
+        with pytest.raises(ValueError):
+            self.hass.add_job(None, 'test_arg')
+
 
 class TestEvent(unittest.TestCase):
     """A Test Event class."""