diff --git a/homeassistant/components/zwave_js/api.py b/homeassistant/components/zwave_js/api.py
index 599183eba7e..055115db7b9 100644
--- a/homeassistant/components/zwave_js/api.py
+++ b/homeassistant/components/zwave_js/api.py
@@ -371,6 +371,7 @@ def websocket_get_config_parameters(
         metadata = zwave_value.metadata
         result[value_id] = {
             "property": zwave_value.property_,
+            "property_key": zwave_value.property_key,
             "configuration_value_type": zwave_value.configuration_value_type.value,
             "metadata": {
                 "description": metadata.description,
diff --git a/tests/components/zwave_js/test_api.py b/tests/components/zwave_js/test_api.py
index aa085836b65..dd8679ddf73 100644
--- a/tests/components/zwave_js/test_api.py
+++ b/tests/components/zwave_js/test_api.py
@@ -73,10 +73,14 @@ async def test_websocket_api(hass, integration, multisensor_6, hass_ws_client):
     assert len(result) == 61
     key = "52-112-0-2"
     assert result[key]["property"] == 2
+    assert result[key]["property_key"] is None
     assert result[key]["metadata"]["type"] == "number"
     assert result[key]["configuration_value_type"] == "enumerated"
     assert result[key]["metadata"]["states"]
 
+    key = "52-112-0-201-255"
+    assert result[key]["property_key"] == 255
+
     # Test getting non-existent node fails
     await ws_client.send_json(
         {