diff --git a/homeassistant/components/sun/sensor.py b/homeassistant/components/sun/sensor.py
index 93460eaf1041e7..384e356fdd6eac 100644
--- a/homeassistant/components/sun/sensor.py
+++ b/homeassistant/components/sun/sensor.py
@@ -26,7 +26,7 @@
 ENTITY_ID_SENSOR_FORMAT = SENSOR_DOMAIN + ".sun_{}"
 
 
-@dataclass(kw_only=True)
+@dataclass(kw_only=True, frozen=True)
 class SunSensorEntityDescription(SensorEntityDescription):
     """Describes a Sun sensor entity."""