diff --git a/homeassistant/components/matter/sensor.py b/homeassistant/components/matter/sensor.py
index 4e9d27aed3e..5e02fe640ab 100644
--- a/homeassistant/components/matter/sensor.py
+++ b/homeassistant/components/matter/sensor.py
@@ -48,8 +48,8 @@ AIR_QUALITY_MAP = {
     clusters.AirQuality.Enums.AirQualityEnum.kFair: "fair",
     clusters.AirQuality.Enums.AirQualityEnum.kGood: "good",
     clusters.AirQuality.Enums.AirQualityEnum.kModerate: "moderate",
-    clusters.AirQuality.Enums.AirQualityEnum.kUnknown: "unknown",
-    clusters.AirQuality.Enums.AirQualityEnum.kUnknownEnumValue: "unknown",
+    clusters.AirQuality.Enums.AirQualityEnum.kUnknown: None,
+    clusters.AirQuality.Enums.AirQualityEnum.kUnknownEnumValue: None,
 }
 
 
@@ -305,7 +305,7 @@ DISCOVERY_SCHEMAS = [
             device_class=SensorDeviceClass.ENUM,
             state_class=None,
             # convert to set first to remove the duplicate unknown value
-            options=list(set(AIR_QUALITY_MAP.values())),
+            options=[x for x in AIR_QUALITY_MAP.values() if x is not None],
             measurement_to_ha=lambda x: AIR_QUALITY_MAP[x],
         ),
         entity_class=MatterSensor,
diff --git a/homeassistant/components/matter/strings.json b/homeassistant/components/matter/strings.json
index 14de4105f40..3ecaf6a8151 100644
--- a/homeassistant/components/matter/strings.json
+++ b/homeassistant/components/matter/strings.json
@@ -157,8 +157,7 @@
           "poor": "Poor",
           "fair": "Fair",
           "good": "Good",
-          "moderate": "Moderate",
-          "unknown": "Unknown"
+          "moderate": "Moderate"
         }
       },
       "flow": {
diff --git a/tests/components/matter/test_sensor.py b/tests/components/matter/test_sensor.py
index 20ecef8609b..c8f89eb8f0c 100644
--- a/tests/components/matter/test_sensor.py
+++ b/tests/components/matter/test_sensor.py
@@ -499,7 +499,6 @@ async def test_air_purifier_sensor(
         "fair",
         "good",
         "moderate",
-        "unknown",
     ]
     assert set(state.attributes["options"]) == set(expected_options)
     assert state.attributes["device_class"] == "enum"