diff --git a/homeassistant/components/sensor/icons.json b/homeassistant/components/sensor/icons.json
index fac1a681b44..59d57da2803 100644
--- a/homeassistant/components/sensor/icons.json
+++ b/homeassistant/components/sensor/icons.json
@@ -118,6 +118,9 @@
     "pm25": {
       "default": "mdi:molecule"
     },
+    "pm4": {
+      "default": "mdi:molecule"
+    },
     "power": {
       "default": "mdi:flash"
     },