diff --git a/homeassistant/components/lg_thinq/number.py b/homeassistant/components/lg_thinq/number.py
index 0f2cf1f67b9f..5c40301be228 100644
--- a/homeassistant/components/lg_thinq/number.py
+++ b/homeassistant/components/lg_thinq/number.py
@@ -101,6 +101,9 @@ DEVICE_TYPE_NUMBER_MAP: dict[DeviceType, tuple[NumberEntityDescription, ...]] =
         TIMER_NUMBER_DESC[ThinQProperty.RELATIVE_HOUR_TO_STOP],
         TIMER_NUMBER_DESC[ThinQProperty.SLEEP_TIMER_RELATIVE_HOUR_TO_STOP],
     ),
+    DeviceType.AIR_PURIFIER: (
+        TIMER_NUMBER_DESC[ThinQProperty.SLEEP_TIMER_RELATIVE_HOUR_TO_STOP],
+    ),
     DeviceType.AIR_PURIFIER_FAN: (
         NUMBER_DESC[ThinQProperty.WIND_TEMPERATURE],
         TIMER_NUMBER_DESC[ThinQProperty.SLEEP_TIMER_RELATIVE_HOUR_TO_STOP],
diff --git a/tests/components/lg_thinq/conftest.py b/tests/components/lg_thinq/conftest.py
index c373c5dac5da..96c916a64a98 100644
--- a/tests/components/lg_thinq/conftest.py
+++ b/tests/components/lg_thinq/conftest.py
@@ -117,9 +117,10 @@ def mock_thinq_mqtt_client() -> Generator[None]:
         "air_conditioner",
         "air_conditioner1",
         "air_conditioner2",
-        "washer",
+        "air_purifier",
         "dehumidifier",
         "kimchi_refrigerator",
+        "washer",
     ]
 )
 def device_fixture(request: pytest.FixtureRequest) -> Generator[str]:
diff --git a/tests/components/lg_thinq/fixtures/air_purifier/device.json b/tests/components/lg_thinq/fixtures/air_purifier/device.json
new file mode 100644
index 000000000000..770c02c19a5a
--- /dev/null
+++ b/tests/components/lg_thinq/fixtures/air_purifier/device.json
@@ -0,0 +1,9 @@
+{
+  "deviceId": "MW2-5E747ABC-6542-4DEF-AA89-4EC4353B2E90",
+  "deviceInfo": {
+    "deviceType": "DEVICE_AIR_PURIFIER",
+    "modelName": "AIR_910604_WW",
+    "alias": "Test air purifier",
+    "reportable": true
+  }
+}
diff --git a/tests/components/lg_thinq/fixtures/air_purifier/energy_profile.json b/tests/components/lg_thinq/fixtures/air_purifier/energy_profile.json
new file mode 100644
index 000000000000..05dd9622432b
--- /dev/null
+++ b/tests/components/lg_thinq/fixtures/air_purifier/energy_profile.json
@@ -0,0 +1,4 @@
+{
+  "resultCode": "0000",
+  "result": {}
+}
diff --git a/tests/components/lg_thinq/fixtures/air_purifier/profile.json b/tests/components/lg_thinq/fixtures/air_purifier/profile.json
new file mode 100644
index 000000000000..e64a65add071
--- /dev/null
+++ b/tests/components/lg_thinq/fixtures/air_purifier/profile.json
@@ -0,0 +1,20 @@
+{
+  "property": {
+    "operation": {
+      "airPurifierOperationMode": {
+        "mode": ["r", "w"],
+        "type": "enum",
+        "value": {
+          "r": ["POWER_ON", "POWER_OFF"],
+          "w": ["POWER_ON", "POWER_OFF"]
+        }
+      }
+    },
+    "sleepTimer": {
+      "relativeHourToStop": {
+        "mode": ["r", "w"],
+        "type": "number"
+      }
+    }
+  }
+}
diff --git a/tests/components/lg_thinq/fixtures/air_purifier/status.json b/tests/components/lg_thinq/fixtures/air_purifier/status.json
new file mode 100644
index 000000000000..a440ffe4b526
--- /dev/null
+++ b/tests/components/lg_thinq/fixtures/air_purifier/status.json
@@ -0,0 +1,8 @@
+{
+  "operation": {
+    "airPurifierOperationMode": "POWER_ON"
+  },
+  "sleepTimer": {
+    "relativeHourToStop": 4
+  }
+}
diff --git a/tests/components/lg_thinq/snapshots/test_number.ambr b/tests/components/lg_thinq/snapshots/test_number.ambr
index 3263b8818b2e..32aac596932f 100644
--- a/tests/components/lg_thinq/snapshots/test_number.ambr
+++ b/tests/components/lg_thinq/snapshots/test_number.ambr
@@ -179,3 +179,63 @@
     'state': '0',
   })
 # ---
+# name: test_number_entities[air_purifier][number.test_air_purifier_sleep_timer-entry]
+  EntityRegistryEntrySnapshot({
+    'aliases': list([
+      None,
+    ]),
+    'area_id': None,
+    'capabilities': dict({
+      <NumberEntityCapabilityAttribute.MAX: 'max'>: 100.0,
+      <NumberEntityCapabilityAttribute.MIN: 'min'>: 0.0,
+      <NumberEntityCapabilityAttribute.MODE: 'mode'>: <NumberMode.BOX: 'box'>,
+      <NumberEntityCapabilityAttribute.STEP: 'step'>: 1.0,
+    }),
+    'config_entry_id': <ANY>,
+    'config_subentry_id': <ANY>,
+    'device_class': None,
+    'device_id': <ANY>,
+    'disabled_by': None,
+    'domain': 'number',
+    'entity_category': None,
+    'entity_id': 'number.test_air_purifier_sleep_timer',
+    'has_entity_name': True,
+    'hidden_by': None,
+    'icon': None,
+    'id': <ANY>,
+    'labels': set({
+    }),
+    'name': None,
+    'object_id_base': 'Sleep timer',
+    'options': dict({
+    }),
+    'original_device_class': None,
+    'original_icon': None,
+    'original_name': 'Sleep timer',
+    'platform': 'lg_thinq',
+    'previous_unique_id': None,
+    'suggested_object_id': None,
+    'supported_features': 0,
+    'translation_key': <Property.SLEEP_TIMER_RELATIVE_HOUR_TO_STOP: 'sleep_timer_relative_hour_to_stop'>,
+    'unique_id': 'MW2-5E747ABC-6542-4DEF-AA89-4EC4353B2E90_sleep_timer_relative_hour_to_stop',
+    'unit_of_measurement': <UnitOfTime.HOURS: 'h'>,
+  })
+# ---
+# name: test_number_entities[air_purifier][number.test_air_purifier_sleep_timer-state]
+  StateSnapshot({
+    'attributes': ReadOnlyDict({
+      <EntityStateAttribute.FRIENDLY_NAME: 'friendly_name'>: 'Test air purifier Sleep timer',
+      <NumberEntityCapabilityAttribute.MAX: 'max'>: 100.0,
+      <NumberEntityCapabilityAttribute.MIN: 'min'>: 0.0,
+      <NumberEntityCapabilityAttribute.MODE: 'mode'>: <NumberMode.BOX: 'box'>,
+      <NumberEntityCapabilityAttribute.STEP: 'step'>: 1.0,
+      <EntityStateAttribute.UNIT_OF_MEASUREMENT: 'unit_of_measurement'>: <UnitOfTime.HOURS: 'h'>,
+    }),
+    'context': <ANY>,
+    'entity_id': 'number.test_air_purifier_sleep_timer',
+    'last_changed': <ANY>,
+    'last_reported': <ANY>,
+    'last_updated': <ANY>,
+    'state': '4',
+  })
+# ---
diff --git a/tests/components/lg_thinq/test_number.py b/tests/components/lg_thinq/test_number.py
index a740cb500c5c..0ba49b117284 100644
--- a/tests/components/lg_thinq/test_number.py
+++ b/tests/components/lg_thinq/test_number.py
@@ -15,7 +15,9 @@ from tests.common import MockConfigEntry, snapshot_platform
 
 
 @pytest.mark.usefixtures("entity_registry_enabled_by_default")
-@pytest.mark.parametrize("device_fixture", ["air_conditioner", "washer"])
+@pytest.mark.parametrize(
+    "device_fixture", ["air_conditioner", "air_purifier", "washer"]
+)
 async def test_number_entities(
     hass: HomeAssistant,
     snapshot: SnapshotAssertion,