diff --git a/homeassistant/components/airgradient/sensor.py b/homeassistant/components/airgradient/sensor.py
index e2fc580fce5..f21f13b80ab 100644
--- a/homeassistant/components/airgradient/sensor.py
+++ b/homeassistant/components/airgradient/sensor.py
@@ -103,6 +103,7 @@ SENSOR_TYPES: tuple[AirGradientSensorEntityDescription, ...] = (
     AirGradientSensorEntityDescription(
         key="pm003",
         translation_key="pm003_count",
+        native_unit_of_measurement="particles/dL",
         state_class=SensorStateClass.MEASUREMENT,
         value_fn=lambda status: status.pm003_count,
     ),
diff --git a/homeassistant/components/airgradient/strings.json b/homeassistant/components/airgradient/strings.json
index 3b1e9f9ee41..20322eed33c 100644
--- a/homeassistant/components/airgradient/strings.json
+++ b/homeassistant/components/airgradient/strings.json
@@ -48,7 +48,7 @@
         "name": "Nitrogen index"
       },
       "pm003_count": {
-        "name": "PM0.3 count"
+        "name": "PM0.3"
       },
       "raw_total_volatile_organic_component": {
         "name": "Raw total VOC"
diff --git a/tests/components/airgradient/snapshots/test_sensor.ambr b/tests/components/airgradient/snapshots/test_sensor.ambr
index 27d8043a395..b9b6be41ff4 100644
--- a/tests/components/airgradient/snapshots/test_sensor.ambr
+++ b/tests/components/airgradient/snapshots/test_sensor.ambr
@@ -150,7 +150,7 @@
     'state': '1',
   })
 # ---
-# name: test_all_entities[sensor.airgradient_pm0_3_count-entry]
+# name: test_all_entities[sensor.airgradient_pm0_3-entry]
   EntityRegistryEntrySnapshot({
     'aliases': set({
     }),
@@ -164,7 +164,7 @@
     'disabled_by': None,
     'domain': 'sensor',
     'entity_category': None,
-    'entity_id': 'sensor.airgradient_pm0_3_count',
+    'entity_id': 'sensor.airgradient_pm0_3',
     'has_entity_name': True,
     'hidden_by': None,
     'icon': None,
@@ -176,23 +176,24 @@
     }),
     'original_device_class': None,
     'original_icon': None,
-    'original_name': 'PM0.3 count',
+    'original_name': 'PM0.3',
     'platform': 'airgradient',
     'previous_unique_id': None,
     'supported_features': 0,
     'translation_key': 'pm003_count',
     'unique_id': '84fce612f5b8-pm003',
-    'unit_of_measurement': None,
+    'unit_of_measurement': 'particles/dL',
   })
 # ---
-# name: test_all_entities[sensor.airgradient_pm0_3_count-state]
+# name: test_all_entities[sensor.airgradient_pm0_3-state]
   StateSnapshot({
     'attributes': ReadOnlyDict({
-      'friendly_name': 'Airgradient PM0.3 count',
+      'friendly_name': 'Airgradient PM0.3',
       'state_class': <SensorStateClass.MEASUREMENT: 'measurement'>,
+      'unit_of_measurement': 'particles/dL',
     }),
     'context': <ANY>,
-    'entity_id': 'sensor.airgradient_pm0_3_count',
+    'entity_id': 'sensor.airgradient_pm0_3',
     'last_changed': <ANY>,
     'last_reported': <ANY>,
     'last_updated': <ANY>,