diff --git a/homeassistant/components/zwave_js/api.py b/homeassistant/components/zwave_js/api.py
index b43528fe358d0b4cae75821d33ce6dc6ec54c035..0339023b954f8c2ac93f61c79963e62550a7fe09 100644
--- a/homeassistant/components/zwave_js/api.py
+++ b/homeassistant/components/zwave_js/api.py
@@ -740,6 +740,7 @@ async def websocket_add_node(
             "status": node.status,
             "ready": node.ready,
             "low_security": event["result"].get("lowSecurity", False),
+            "low_security_reason": event["result"].get("lowSecurityReason"),
         }
         connection.send_message(
             websocket_api.event_message(
diff --git a/tests/components/zwave_js/test_api.py b/tests/components/zwave_js/test_api.py
index f636401a942433de0cd7755394261631ed46ac4a..1d4ee7d4d86ca3a527709939f61969e02654b78f 100644
--- a/tests/components/zwave_js/test_api.py
+++ b/tests/components/zwave_js/test_api.py
@@ -590,6 +590,7 @@ async def test_add_node(
         "status": 0,
         "ready": False,
         "low_security": False,
+        "low_security_reason": None,
     }
     assert msg["event"]["node"] == node_details