diff --git a/homeassistant/components/device_tracker/__init__.py b/homeassistant/components/device_tracker/__init__.py
index af33453c9d5..7d8449197de 100644
--- a/homeassistant/components/device_tracker/__init__.py
+++ b/homeassistant/components/device_tracker/__init__.py
@@ -580,6 +580,7 @@ class Device(RestoreEntity):
             return
         self._state = state.state
         self.last_update_home = (state.state == STATE_HOME)
+        self.last_seen = dt_util.utcnow()
 
         for attr, var in (
                 (ATTR_SOURCE_TYPE, 'source_type'),