diff --git a/homeassistant/components/eurotronic_cometblue/__init__.py b/homeassistant/components/eurotronic_cometblue/__init__.py
index 1ef3d6ccf45..0042091ce58 100644
--- a/homeassistant/components/eurotronic_cometblue/__init__.py
+++ b/homeassistant/components/eurotronic_cometblue/__init__.py
@@ -57,6 +57,7 @@ async def async_setup_entry(hass: HomeAssistant, entry: CometBlueConfigEntry) ->
     device_registry.async_get_or_create(
         config_entry_id=entry.entry_id,
         identifiers={(DOMAIN, address)},
+        connections={(dr.CONNECTION_BLUETOOTH, address)},
         name=f"{ble_device_info['model']} {cometblue_device.device.address}",
         manufacturer=ble_device_info["manufacturer"],
         model=ble_device_info["model"],
diff --git a/tests/components/eurotronic_cometblue/snapshots/test_init.ambr b/tests/components/eurotronic_cometblue/snapshots/test_init.ambr
new file mode 100644
index 00000000000..e7a6d8a3ebd
--- /dev/null
+++ b/tests/components/eurotronic_cometblue/snapshots/test_init.ambr
@@ -0,0 +1,36 @@
+# serializer version: 1
+# name: test_device_registry
+  DeviceRegistryEntrySnapshot({
+    'area_id': None,
+    'config_entries': <ANY>,
+    'config_entries_subentries': <ANY>,
+    'configuration_url': None,
+    'connections': set({
+      tuple(
+        'bluetooth',
+        'aa:bb:cc:dd:ee:ff',
+      ),
+    }),
+    'disabled_by': None,
+    'entry_type': None,
+    'hw_version': None,
+    'id': <ANY>,
+    'identifiers': set({
+      tuple(
+        'eurotronic_cometblue',
+        'aa:bb:cc:dd:ee:ff',
+      ),
+    }),
+    'labels': set({
+    }),
+    'manufacturer': 'Eurotronic GmbH',
+    'model': 'Comet Blue',
+    'model_id': None,
+    'name': 'Comet Blue aa:bb:cc:dd:ee:ff',
+    'name_by_user': None,
+    'primary_config_entry': <ANY>,
+    'serial_number': None,
+    'sw_version': '0.0.10',
+    'via_device_id': None,
+  })
+# ---
diff --git a/tests/components/eurotronic_cometblue/test_init.py b/tests/components/eurotronic_cometblue/test_init.py
new file mode 100644
index 00000000000..ed544950171
--- /dev/null
+++ b/tests/components/eurotronic_cometblue/test_init.py
@@ -0,0 +1,25 @@
+"""Test the Eurotronic Comet Blue integration setup."""
+
+from syrupy.assertion import SnapshotAssertion
+
+from homeassistant.components.eurotronic_cometblue.const import DOMAIN
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers import device_registry as dr
+
+from . import FIXTURE_MAC
+from .conftest import setup_with_selected_platforms
+
+from tests.common import MockConfigEntry
+
+
+async def test_device_registry(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    device_registry: dr.DeviceRegistry,
+    snapshot: SnapshotAssertion,
+) -> None:
+    """Test the device registry entry, including the Bluetooth connection."""
+    await setup_with_selected_platforms(hass, mock_config_entry)
+
+    device_entry = device_registry.async_get_device(identifiers={(DOMAIN, FIXTURE_MAC)})
+    assert device_entry == snapshot