diff --git a/homeassistant/components/mqtt/alarm_control_panel.py b/homeassistant/components/mqtt/alarm_control_panel.py
index 72b01f3087b..dfdf2dbfb26 100644
--- a/homeassistant/components/mqtt/alarm_control_panel.py
+++ b/homeassistant/components/mqtt/alarm_control_panel.py
@@ -97,7 +97,7 @@ PLATFORM_SCHEMA = mqtt.MQTT_BASE_PLATFORM_SCHEMA.extend(
     }
 ).extend(MQTT_ENTITY_COMMON_SCHEMA.schema)
 
-DISCOVERY_SCHEMA = PLATFORM_SCHEMA.extend({}, extra=vol.ALLOW_EXTRA)
+DISCOVERY_SCHEMA = PLATFORM_SCHEMA.extend({}, extra=vol.REMOVE_EXTRA)
 
 
 async def async_setup_platform(