diff --git a/homeassistant/components/binary_sensor/__init__.py b/homeassistant/components/binary_sensor/__init__.py
index aff7f9a3135..c9301eb7978 100644
--- a/homeassistant/components/binary_sensor/__init__.py
+++ b/homeassistant/components/binary_sensor/__init__.py
@@ -18,6 +18,7 @@ from homeassistant.helpers.config_validation import (  # noqa: F401
 from homeassistant.helpers.entity import Entity, EntityDescription
 from homeassistant.helpers.entity_component import EntityComponent
 from homeassistant.helpers.typing import ConfigType, StateType
+from homeassistant.util.enum import StrEnum
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -26,118 +27,124 @@ SCAN_INTERVAL = timedelta(seconds=30)
 
 ENTITY_ID_FORMAT = DOMAIN + ".{}"
 
-# On means low, Off means normal
-DEVICE_CLASS_BATTERY = "battery"
 
-# On means charging, Off means not charging
-DEVICE_CLASS_BATTERY_CHARGING = "battery_charging"
+class BinarySensorDeviceClass(StrEnum):
+    """Device class for binary sensors."""
 
-# On means cold, Off means normal
-DEVICE_CLASS_COLD = "cold"
+    # On means low, Off means normal
+    BATTERY = "battery"
 
-# On means connected, Off means disconnected
-DEVICE_CLASS_CONNECTIVITY = "connectivity"
+    # On means charging, Off means not charging
+    BATTERY_CHARGING = "battery_charging"
 
-# On means open, Off means closed
-DEVICE_CLASS_DOOR = "door"
+    # On means cold, Off means normal
+    COLD = "cold"
 
-# On means open, Off means closed
-DEVICE_CLASS_GARAGE_DOOR = "garage_door"
+    # On means connected, Off means disconnected
+    CONNECTIVITY = "connectivity"
 
-# On means gas detected, Off means no gas (clear)
-DEVICE_CLASS_GAS = "gas"
+    # On means open, Off means closed
+    DOOR = "door"
 
-# On means hot, Off means normal
-DEVICE_CLASS_HEAT = "heat"
+    # On means open, Off means closed
+    GARAGE_DOOR = "garage_door"
 
-# On means light detected, Off means no light
-DEVICE_CLASS_LIGHT = "light"
+    # On means gas detected, Off means no gas (clear)
+    GAS = "gas"
 
-# On means open (unlocked), Off means closed (locked)
-DEVICE_CLASS_LOCK = "lock"
+    # On means hot, Off means normal
+    HEAT = "heat"
 
-# On means wet, Off means dry
-DEVICE_CLASS_MOISTURE = "moisture"
+    # On means light detected, Off means no light
+    LIGHT = "light"
 
-# On means motion detected, Off means no motion (clear)
-DEVICE_CLASS_MOTION = "motion"
+    # On means open (unlocked), Off means closed (locked)
+    LOCK = "lock"
 
-# On means moving, Off means not moving (stopped)
-DEVICE_CLASS_MOVING = "moving"
+    # On means wet, Off means dry
+    MOISTURE = "moisture"
 
-# On means occupied, Off means not occupied (clear)
-DEVICE_CLASS_OCCUPANCY = "occupancy"
+    # On means motion detected, Off means no motion (clear)
+    MOTION = "motion"
 
-# On means open, Off means closed
-DEVICE_CLASS_OPENING = "opening"
+    # On means moving, Off means not moving (stopped)
+    MOVING = "moving"
 
-# On means plugged in, Off means unplugged
-DEVICE_CLASS_PLUG = "plug"
+    # On means occupied, Off means not occupied (clear)
+    OCCUPANCY = "occupancy"
 
-# On means power detected, Off means no power
-DEVICE_CLASS_POWER = "power"
+    # On means open, Off means closed
+    OPENING = "opening"
 
-# On means home, Off means away
-DEVICE_CLASS_PRESENCE = "presence"
+    # On means plugged in, Off means unplugged
+    PLUG = "plug"
 
-# On means problem detected, Off means no problem (OK)
-DEVICE_CLASS_PROBLEM = "problem"
+    # On means power detected, Off means no power
+    POWER = "power"
 
-# On means running, Off means not running
-DEVICE_CLASS_RUNNING = "running"
+    # On means home, Off means away
+    PRESENCE = "presence"
 
-# On means unsafe, Off means safe
-DEVICE_CLASS_SAFETY = "safety"
+    # On means problem detected, Off means no problem (OK)
+    PROBLEM = "problem"
 
-# On means smoke detected, Off means no smoke (clear)
-DEVICE_CLASS_SMOKE = "smoke"
+    # On means running, Off means not running
+    RUNNING = "running"
 
-# On means sound detected, Off means no sound (clear)
-DEVICE_CLASS_SOUND = "sound"
+    # On means unsafe, Off means safe
+    SAFETY = "safety"
 
-# On means tampering detected, Off means no tampering (clear)
-DEVICE_CLASS_TAMPER = "tamper"
+    # On means smoke detected, Off means no smoke (clear)
+    SMOKE = "smoke"
 
-# On means update available, Off means up-to-date
-DEVICE_CLASS_UPDATE = "update"
+    # On means sound detected, Off means no sound (clear)
+    SOUND = "sound"
 
-# On means vibration detected, Off means no vibration
-DEVICE_CLASS_VIBRATION = "vibration"
+    # On means tampering detected, Off means no tampering (clear)
+    TAMPER = "tamper"
 
-# On means open, Off means closed
-DEVICE_CLASS_WINDOW = "window"
+    # On means update available, Off means up-to-date
+    UPDATE = "update"
 
-DEVICE_CLASSES = [
-    DEVICE_CLASS_BATTERY,
-    DEVICE_CLASS_BATTERY_CHARGING,
-    DEVICE_CLASS_COLD,
-    DEVICE_CLASS_CONNECTIVITY,
-    DEVICE_CLASS_DOOR,
-    DEVICE_CLASS_GARAGE_DOOR,
-    DEVICE_CLASS_GAS,
-    DEVICE_CLASS_HEAT,
-    DEVICE_CLASS_LIGHT,
-    DEVICE_CLASS_LOCK,
-    DEVICE_CLASS_MOISTURE,
-    DEVICE_CLASS_MOTION,
-    DEVICE_CLASS_MOVING,
-    DEVICE_CLASS_OCCUPANCY,
-    DEVICE_CLASS_OPENING,
-    DEVICE_CLASS_PLUG,
-    DEVICE_CLASS_POWER,
-    DEVICE_CLASS_PRESENCE,
-    DEVICE_CLASS_PROBLEM,
-    DEVICE_CLASS_RUNNING,
-    DEVICE_CLASS_SAFETY,
-    DEVICE_CLASS_SMOKE,
-    DEVICE_CLASS_SOUND,
-    DEVICE_CLASS_TAMPER,
-    DEVICE_CLASS_UPDATE,
-    DEVICE_CLASS_VIBRATION,
-    DEVICE_CLASS_WINDOW,
-]
+    # On means vibration detected, Off means no vibration
+    VIBRATION = "vibration"
 
-DEVICE_CLASSES_SCHEMA = vol.All(vol.Lower, vol.In(DEVICE_CLASSES))
+    # On means open, Off means closed
+    WINDOW = "window"
+
+
+DEVICE_CLASSES_SCHEMA = vol.All(vol.Lower, vol.Coerce(BinarySensorDeviceClass))
+
+# DEVICE_CLASS* below are deprecated as of 2021.12
+# use the BinarySensorDeviceClass enum instead.
+DEVICE_CLASSES = [cls.value for cls in BinarySensorDeviceClass]
+DEVICE_CLASS_BATTERY = BinarySensorDeviceClass.BATTERY.value
+DEVICE_CLASS_BATTERY_CHARGING = BinarySensorDeviceClass.BATTERY_CHARGING.value
+DEVICE_CLASS_COLD = BinarySensorDeviceClass.COLD.value
+DEVICE_CLASS_CONNECTIVITY = BinarySensorDeviceClass.CONNECTIVITY.value
+DEVICE_CLASS_DOOR = BinarySensorDeviceClass.DOOR.value
+DEVICE_CLASS_GARAGE_DOOR = BinarySensorDeviceClass.GARAGE_DOOR.value
+DEVICE_CLASS_GAS = BinarySensorDeviceClass.GAS.value
+DEVICE_CLASS_HEAT = BinarySensorDeviceClass.HEAT.value
+DEVICE_CLASS_LIGHT = BinarySensorDeviceClass.LIGHT.value
+DEVICE_CLASS_LOCK = BinarySensorDeviceClass.LOCK.value
+DEVICE_CLASS_MOISTURE = BinarySensorDeviceClass.MOISTURE.value
+DEVICE_CLASS_MOTION = BinarySensorDeviceClass.MOTION.value
+DEVICE_CLASS_MOVING = BinarySensorDeviceClass.MOVING.value
+DEVICE_CLASS_OCCUPANCY = BinarySensorDeviceClass.OCCUPANCY.value
+DEVICE_CLASS_OPENING = BinarySensorDeviceClass.OPENING.value
+DEVICE_CLASS_PLUG = BinarySensorDeviceClass.PLUG.value
+DEVICE_CLASS_POWER = BinarySensorDeviceClass.POWER.value
+DEVICE_CLASS_PRESENCE = BinarySensorDeviceClass.PRESENCE.value
+DEVICE_CLASS_PROBLEM = BinarySensorDeviceClass.PROBLEM.value
+DEVICE_CLASS_RUNNING = BinarySensorDeviceClass.RUNNING.value
+DEVICE_CLASS_SAFETY = BinarySensorDeviceClass.SAFETY.value
+DEVICE_CLASS_SMOKE = BinarySensorDeviceClass.SMOKE.value
+DEVICE_CLASS_SOUND = BinarySensorDeviceClass.SOUND.value
+DEVICE_CLASS_TAMPER = BinarySensorDeviceClass.TAMPER.value
+DEVICE_CLASS_UPDATE = BinarySensorDeviceClass.UPDATE.value
+DEVICE_CLASS_VIBRATION = BinarySensorDeviceClass.VIBRATION.value
+DEVICE_CLASS_WINDOW = BinarySensorDeviceClass.WINDOW.value
 
 
 async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
@@ -166,14 +173,26 @@ async def async_unload_entry(hass: HomeAssistant, entry: ConfigEntry) -> bool:
 class BinarySensorEntityDescription(EntityDescription):
     """A class that describes binary sensor entities."""
 
+    device_class: BinarySensorDeviceClass | str | None = None
+
 
 class BinarySensorEntity(Entity):
     """Represent a binary sensor."""
 
     entity_description: BinarySensorEntityDescription
+    _attr_device_class: BinarySensorDeviceClass | str | None
     _attr_is_on: bool | None = None
     _attr_state: None = None
 
+    @property
+    def device_class(self) -> BinarySensorDeviceClass | str | None:
+        """Return the class of this entity."""
+        if hasattr(self, "_attr_device_class"):
+            return self._attr_device_class
+        if hasattr(self, "entity_description"):
+            return self.entity_description.device_class
+        return None
+
     @property
     def is_on(self) -> bool | None:
         """Return true if the binary sensor is on."""
diff --git a/homeassistant/components/demo/binary_sensor.py b/homeassistant/components/demo/binary_sensor.py
index 7cf96d33f5c..8710308fc67 100644
--- a/homeassistant/components/demo/binary_sensor.py
+++ b/homeassistant/components/demo/binary_sensor.py
@@ -1,7 +1,6 @@
 """Demo platform that has two fake binary sensors."""
 from homeassistant.components.binary_sensor import (
-    DEVICE_CLASS_MOISTURE,
-    DEVICE_CLASS_MOTION,
+    BinarySensorDeviceClass,
     BinarySensorEntity,
 )
 from homeassistant.helpers.entity import DeviceInfo
@@ -14,10 +13,13 @@ async def async_setup_platform(hass, config, async_add_entities, discovery_info=
     async_add_entities(
         [
             DemoBinarySensor(
-                "binary_1", "Basement Floor Wet", False, DEVICE_CLASS_MOISTURE
+                "binary_1",
+                "Basement Floor Wet",
+                False,
+                BinarySensorDeviceClass.MOISTURE,
             ),
             DemoBinarySensor(
-                "binary_2", "Movement Backyard", True, DEVICE_CLASS_MOTION
+                "binary_2", "Movement Backyard", True, BinarySensorDeviceClass.MOTION
             ),
         ]
     )
@@ -31,7 +33,13 @@ async def async_setup_entry(hass, config_entry, async_add_entities):
 class DemoBinarySensor(BinarySensorEntity):
     """representation of a Demo binary sensor."""
 
-    def __init__(self, unique_id, name, state, device_class):
+    def __init__(
+        self,
+        unique_id: str,
+        name: str,
+        state: bool,
+        device_class: BinarySensorDeviceClass,
+    ) -> None:
         """Initialize the demo sensor."""
         self._unique_id = unique_id
         self._name = name
@@ -55,7 +63,7 @@ class DemoBinarySensor(BinarySensorEntity):
         return self._unique_id
 
     @property
-    def device_class(self):
+    def device_class(self) -> BinarySensorDeviceClass:
         """Return the class of this sensor."""
         return self._sensor_type
 
diff --git a/homeassistant/components/sia/binary_sensor.py b/homeassistant/components/sia/binary_sensor.py
index eec4f9b2717..980596367b2 100644
--- a/homeassistant/components/sia/binary_sensor.py
+++ b/homeassistant/components/sia/binary_sensor.py
@@ -8,9 +8,7 @@ from typing import Any
 from pysiaalarm import SIAEvent
 
 from homeassistant.components.binary_sensor import (
-    DEVICE_CLASS_MOISTURE,
-    DEVICE_CLASS_POWER,
-    DEVICE_CLASS_SMOKE,
+    BinarySensorDeviceClass,
     BinarySensorEntity,
 )
 from homeassistant.config_entries import ConfigEntry
@@ -81,11 +79,11 @@ class SIABinarySensorBase(SIABaseEntity, BinarySensorEntity):
         entry: ConfigEntry,
         account_data: dict[str, Any],
         zone: int,
-        device_class: str,
+        device_class: BinarySensorDeviceClass,
     ) -> None:
         """Initialize a base binary sensor."""
-        super().__init__(entry, account_data, zone, device_class)
-
+        super().__init__(entry, account_data, zone)
+        self._attr_device_class = device_class
         self._attr_unique_id = SIA_UNIQUE_ID_FORMAT_BINARY.format(
             self._entry.entry_id, self._account, self._zone, self._attr_device_class
         )
@@ -111,7 +109,7 @@ class SIABinarySensorMoisture(SIABinarySensorBase):
         zone: int,
     ) -> None:
         """Initialize a Moisture binary sensor."""
-        super().__init__(entry, account_data, zone, DEVICE_CLASS_MOISTURE)
+        super().__init__(entry, account_data, zone, BinarySensorDeviceClass.MOISTURE)
         self._attr_entity_registry_enabled_default = False
 
     def update_state(self, sia_event: SIAEvent) -> None:
@@ -132,7 +130,7 @@ class SIABinarySensorSmoke(SIABinarySensorBase):
         zone: int,
     ) -> None:
         """Initialize a Smoke binary sensor."""
-        super().__init__(entry, account_data, zone, DEVICE_CLASS_SMOKE)
+        super().__init__(entry, account_data, zone, BinarySensorDeviceClass.SMOKE)
         self._attr_entity_registry_enabled_default = False
 
     def update_state(self, sia_event: SIAEvent) -> None:
@@ -152,7 +150,9 @@ class SIABinarySensorPower(SIABinarySensorBase):
         account_data: dict[str, Any],
     ) -> None:
         """Initialize a Power binary sensor."""
-        super().__init__(entry, account_data, SIA_HUB_ZONE, DEVICE_CLASS_POWER)
+        super().__init__(
+            entry, account_data, SIA_HUB_ZONE, BinarySensorDeviceClass.POWER
+        )
         self._attr_entity_registry_enabled_default = True
 
     def update_state(self, sia_event: SIAEvent) -> None:
diff --git a/homeassistant/components/sia/sia_entity_base.py b/homeassistant/components/sia/sia_entity_base.py
index 14334d1f8cb..f4937e326eb 100644
--- a/homeassistant/components/sia/sia_entity_base.py
+++ b/homeassistant/components/sia/sia_entity_base.py
@@ -29,13 +29,13 @@ class SIABaseEntity(RestoreEntity):
         entry: ConfigEntry,
         account_data: dict[str, Any],
         zone: int,
-        device_class: str,
+        device_class: str | None = None,
     ) -> None:
         """Create SIABaseEntity object."""
         self._entry: ConfigEntry = entry
         self._account_data: dict[str, Any] = account_data
         self._zone: int = zone
-        self._attr_device_class: str = device_class
+        self._attr_device_class = device_class
 
         self._port: int = self._entry.data[CONF_PORT]
         self._account: str = self._account_data[CONF_ACCOUNT]
diff --git a/homeassistant/components/upcloud/binary_sensor.py b/homeassistant/components/upcloud/binary_sensor.py
index de55a577610..ebdc30b69f1 100644
--- a/homeassistant/components/upcloud/binary_sensor.py
+++ b/homeassistant/components/upcloud/binary_sensor.py
@@ -2,7 +2,11 @@
 
 import voluptuous as vol
 
-from homeassistant.components.binary_sensor import PLATFORM_SCHEMA, BinarySensorEntity
+from homeassistant.components.binary_sensor import (
+    PLATFORM_SCHEMA,
+    BinarySensorDeviceClass,
+    BinarySensorEntity,
+)
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.const import CONF_USERNAME
 from homeassistant.core import HomeAssistant
@@ -29,3 +33,5 @@ async def async_setup_entry(
 
 class UpCloudBinarySensor(UpCloudServerEntity, BinarySensorEntity):
     """Representation of an UpCloud server sensor."""
+
+    _attr_device_class = BinarySensorDeviceClass.POWER