diff --git a/homeassistant/components/homekit_controller/sensor.py b/homeassistant/components/homekit_controller/sensor.py
index 6bf8a7fc084..91b62b0d572 100644
--- a/homeassistant/components/homekit_controller/sensor.py
+++ b/homeassistant/components/homekit_controller/sensor.py
@@ -12,6 +12,7 @@ from homeassistant.const import (
     DEVICE_CLASS_TEMPERATURE,
     LIGHT_LUX,
     PERCENTAGE,
+    POWER_WATT,
     TEMP_CELSIUS,
 )
 from homeassistant.core import callback
@@ -29,19 +30,19 @@ SIMPLE_SENSOR = {
         "name": "Real Time Energy",
         "device_class": DEVICE_CLASS_POWER,
         "state_class": STATE_CLASS_MEASUREMENT,
-        "unit": "watts",
+        "unit": POWER_WATT,
     },
     CharacteristicsTypes.Vendor.KOOGEEK_REALTIME_ENERGY: {
         "name": "Real Time Energy",
         "device_class": DEVICE_CLASS_POWER,
         "state_class": STATE_CLASS_MEASUREMENT,
-        "unit": "watts",
+        "unit": POWER_WATT,
     },
     CharacteristicsTypes.Vendor.KOOGEEK_REALTIME_ENERGY_2: {
         "name": "Real Time Energy",
         "device_class": DEVICE_CLASS_POWER,
         "state_class": STATE_CLASS_MEASUREMENT,
-        "unit": "watts",
+        "unit": POWER_WATT,
     },
     CharacteristicsTypes.get_uuid(CharacteristicsTypes.TEMPERATURE_CURRENT): {
         "name": "Current Temperature",
diff --git a/tests/components/homekit_controller/specific_devices/test_koogeek_p1eu.py b/tests/components/homekit_controller/specific_devices/test_koogeek_p1eu.py
index 6302013223d..1761edb3c8c 100644
--- a/tests/components/homekit_controller/specific_devices/test_koogeek_p1eu.py
+++ b/tests/components/homekit_controller/specific_devices/test_koogeek_p1eu.py
@@ -1,5 +1,6 @@
 """Make sure that existing Koogeek P1EU support isn't broken."""
 
+from homeassistant.const import POWER_WATT
 from homeassistant.helpers import device_registry as dr, entity_registry as er
 
 from tests.components.homekit_controller.common import (
@@ -48,6 +49,7 @@ async def test_koogeek_p1eu_setup(hass):
     )
     state = await helper.poll_and_get_state()
     assert state.attributes["friendly_name"] == "Koogeek-P1-A00AA0 - Real Time Energy"
+    assert state.attributes["unit_of_measurement"] == POWER_WATT
 
     # The sensor and switch should be part of the same device
     assert entry.device_id == device.id
diff --git a/tests/components/homekit_controller/specific_devices/test_koogeek_sw2.py b/tests/components/homekit_controller/specific_devices/test_koogeek_sw2.py
index 1d46b633153..768959e0331 100644
--- a/tests/components/homekit_controller/specific_devices/test_koogeek_sw2.py
+++ b/tests/components/homekit_controller/specific_devices/test_koogeek_sw2.py
@@ -6,6 +6,7 @@ This Koogeek device has a custom power sensor that extra handling.
 It should have 2 entities - the actual switch and a sensor for power usage.
 """
 
+from homeassistant.const import POWER_WATT
 from homeassistant.helpers import device_registry as dr, entity_registry as er
 
 from tests.components.homekit_controller.common import (
@@ -58,6 +59,7 @@ async def test_koogeek_ls1_setup(hass):
 
     # Assert that the friendly name is detected correctly
     assert state.attributes["friendly_name"] == "Koogeek-SW2-187A91 - Real Time Energy"
+    assert state.attributes["unit_of_measurement"] == POWER_WATT
 
     device_registry = dr.async_get(hass)