diff --git a/homeassistant/components/harmony/select.py b/homeassistant/components/harmony/select.py
index 3728c4b17a4..a3f059d2c00 100644
--- a/homeassistant/components/harmony/select.py
+++ b/homeassistant/components/harmony/select.py
@@ -16,6 +16,8 @@ from .subscriber import HarmonyCallback
 
 _LOGGER = logging.getLogger(__name__)
 
+TRANSLATABLE_POWER_OFF = "power_off"
+
 
 async def async_setup_entry(
     hass: HomeAssistant, entry: ConfigEntry, async_add_entities: AddEntitiesCallback
@@ -31,6 +33,8 @@ async def async_setup_entry(
 class HarmonyActivitySelect(HarmonyEntity, SelectEntity):
     """Select representation of a Harmony activities."""
 
+    _attr_device_class = f"{DOMAIN}__activities"
+
     def __init__(self, name: str, data: HarmonyData) -> None:
         """Initialize HarmonyActivitySelect class."""
         super().__init__(data=data)
@@ -42,23 +46,27 @@ class HarmonyActivitySelect(HarmonyEntity, SelectEntity):
     @property
     def icon(self) -> str:
         """Return a representative icon."""
-        if not self.available or self.current_option == ACTIVITY_POWER_OFF:
+        if not self.available or self.current_option == TRANSLATABLE_POWER_OFF:
             return "mdi:remote-tv-off"
         return "mdi:remote-tv"
 
     @property
     def options(self) -> list[str]:
         """Return a set of selectable options."""
-        return [ACTIVITY_POWER_OFF] + sorted(self._data.activity_names)
+        return [TRANSLATABLE_POWER_OFF] + sorted(self._data.activity_names)
 
     @property
     def current_option(self) -> str | None:
         """Return the current activity."""
         _, activity_name = self._data.current_activity
+        if activity_name == ACTIVITY_POWER_OFF:
+            return TRANSLATABLE_POWER_OFF
         return activity_name
 
     async def async_select_option(self, option: str) -> None:
         """Change the current activity."""
+        if option == TRANSLATABLE_POWER_OFF:
+            await self._data.async_start_activity(ACTIVITY_POWER_OFF)
         await self._data.async_start_activity(option)
 
     async def async_added_to_hass(self) -> None:
diff --git a/homeassistant/components/harmony/strings.select.json b/homeassistant/components/harmony/strings.select.json
new file mode 100644
index 00000000000..5dbdf1a1c3d
--- /dev/null
+++ b/homeassistant/components/harmony/strings.select.json
@@ -0,0 +1,7 @@
+{
+  "state": {
+    "harmony__activities": {
+      "power_off": "Power Off"
+    }
+  }
+}
diff --git a/homeassistant/components/harmony/translations/select.en.json b/homeassistant/components/harmony/translations/select.en.json
new file mode 100644
index 00000000000..5dbdf1a1c3d
--- /dev/null
+++ b/homeassistant/components/harmony/translations/select.en.json
@@ -0,0 +1,7 @@
+{
+  "state": {
+    "harmony__activities": {
+      "power_off": "Power Off"
+    }
+  }
+}
diff --git a/tests/components/harmony/test_select.py b/tests/components/harmony/test_select.py
index 4607f035893..60bb85ed0c3 100644
--- a/tests/components/harmony/test_select.py
+++ b/tests/components/harmony/test_select.py
@@ -9,6 +9,7 @@ from homeassistant.components.select import (
     SERVICE_SELECT_OPTION,
 )
 from homeassistant.const import (
+    ATTR_DEVICE_CLASS,
     ATTR_ENTITY_ID,
     CONF_HOST,
     CONF_NAME,
@@ -68,11 +69,12 @@ async def test_options(mock_hc, hass, mock_write_config):
     # assert we have all options
     state = hass.states.get(ENTITY_SELECT)
     assert state.attributes.get("options") == [
-        "PowerOff",
+        "power_off",
         "Nile-TV",
         "Play Music",
         "Watch TV",
     ]
+    assert state.attributes.get(ATTR_DEVICE_CLASS) == "harmony__activities"
 
 
 async def test_select_option(mock_hc, hass, mock_write_config):
@@ -94,10 +96,10 @@ async def test_select_option(mock_hc, hass, mock_write_config):
     assert hass.states.is_state(ENTITY_REMOTE, STATE_ON)
     assert hass.states.is_state(ENTITY_SELECT, "Play Music")
 
-    # turn off harmony by selecting PowerOff activity
-    await _select_option_and_wait(hass, ENTITY_SELECT, "PowerOff")
+    # turn off harmony by selecting power_off activity
+    await _select_option_and_wait(hass, ENTITY_SELECT, "power_off")
     assert hass.states.is_state(ENTITY_REMOTE, STATE_OFF)
-    assert hass.states.is_state(ENTITY_SELECT, "PowerOff")
+    assert hass.states.is_state(ENTITY_SELECT, "power_off")
 
 
 async def _select_option_and_wait(hass, entity, option):