diff --git a/homeassistant/components/zha/diagnostics.py b/homeassistant/components/zha/diagnostics.py
index 0fa1de5ff0e..ae68e6d5cca 100644
--- a/homeassistant/components/zha/diagnostics.py
+++ b/homeassistant/components/zha/diagnostics.py
@@ -139,6 +139,19 @@ def get_endpoint_cluster_attr_data(zha_device: ZHADevice) -> dict:
 
 def get_cluster_attr_data(cluster: Cluster) -> dict:
     """Return cluster attribute data."""
+    unsupported_attributes = {}
+    for u_attr in cluster.unsupported_attributes:
+        try:
+            u_attr_def = cluster.find_attribute(u_attr)
+            unsupported_attributes[f"0x{u_attr_def.id:04x}"] = {
+                ATTR_ATTRIBUTE_NAME: u_attr_def.name
+            }
+        except KeyError:
+            if isinstance(u_attr, int):
+                unsupported_attributes[f"0x{u_attr:04x}"] = {}
+            else:
+                unsupported_attributes[u_attr] = {}
+
     return {
         ATTRIBUTES: {
             f"0x{attr_id:04x}": {
@@ -148,10 +161,5 @@ def get_cluster_attr_data(cluster: Cluster) -> dict:
             for attr_id, attr_def in cluster.attributes.items()
             if (attr_value := cluster.get(attr_def.name)) is not None
         },
-        UNSUPPORTED_ATTRIBUTES: {
-            f"0x{cluster.find_attribute(u_attr).id:04x}": {
-                ATTR_ATTRIBUTE_NAME: cluster.find_attribute(u_attr).name
-            }
-            for u_attr in cluster.unsupported_attributes
-        },
+        UNSUPPORTED_ATTRIBUTES: unsupported_attributes,
     }
diff --git a/tests/components/zha/test_diagnostics.py b/tests/components/zha/test_diagnostics.py
index c13bb36c1c0..1f6a731d0fb 100644
--- a/tests/components/zha/test_diagnostics.py
+++ b/tests/components/zha/test_diagnostics.py
@@ -44,7 +44,7 @@ def zigpy_device(zigpy_device_mock):
     """Device tracker zigpy device."""
     endpoints = {
         1: {
-            SIG_EP_INPUT: [security.IasAce.cluster_id],
+            SIG_EP_INPUT: [security.IasAce.cluster_id, security.IasZone.cluster_id],
             SIG_EP_OUTPUT: [],
             SIG_EP_TYPE: zha.DeviceType.IAS_ANCILLARY_CONTROL,
             SIG_EP_PROFILE: zha.PROFILE_ID,
@@ -93,6 +93,22 @@ async def test_diagnostics_for_device(
 ) -> None:
     """Test diagnostics for device."""
     zha_device: ZHADevice = await zha_device_joined(zigpy_device)
+
+    # add unknown unsupported attribute with id and name
+    zha_device.device.endpoints[1].in_clusters[
+        security.IasAce.cluster_id
+    ].unsupported_attributes.update({0x1000, "unknown_attribute_name"})
+
+    # add known unsupported attributes with id and name
+    zha_device.device.endpoints[1].in_clusters[
+        security.IasZone.cluster_id
+    ].unsupported_attributes.update(
+        {
+            security.IasZone.AttributeDefs.num_zone_sensitivity_levels_supported.id,
+            security.IasZone.AttributeDefs.current_zone_sensitivity_level.name,
+        }
+    )
+
     dev_reg = async_get(hass)
     device = dev_reg.async_get_device(identifiers={("zha", str(zha_device.ieee))})
     assert device