diff --git a/homeassistant/components/zwave_js/diagnostics.py b/homeassistant/components/zwave_js/diagnostics.py
index 4f52c41a085..2fe2b17fe1b 100644
--- a/homeassistant/components/zwave_js/diagnostics.py
+++ b/homeassistant/components/zwave_js/diagnostics.py
@@ -65,7 +65,7 @@ def redact_node_state(node_state: NodeDataType) -> NodeDataType:
 
 
 def get_device_entities(
-    hass: HomeAssistant, node: Node, device: dr.DeviceEntry
+    hass: HomeAssistant, node: Node, config_entry: ConfigEntry, device: dr.DeviceEntry
 ) -> list[dict[str, Any]]:
     """Get entities for a device."""
     entity_entries = er.async_entries_for_device(
@@ -73,6 +73,10 @@ def get_device_entities(
     )
     entities = []
     for entry in entity_entries:
+        # Skip entities that are not part of this integration
+        if entry.config_entry_id != config_entry.entry_id:
+            continue
+
         # If the value ID returns as None, we don't need to include this entity
         if (value_id := get_value_id_from_unique_id(entry.unique_id)) is None:
             continue
@@ -142,7 +146,7 @@ async def async_get_device_diagnostics(
     if node_id is None or node_id not in driver.controller.nodes:
         raise ValueError(f"Node for device {device.id} can't be found")
     node = driver.controller.nodes[node_id]
-    entities = get_device_entities(hass, node, device)
+    entities = get_device_entities(hass, node, config_entry, device)
     assert client.version
     node_state = redact_node_state(async_redact_data(node.data, KEYS_TO_REDACT))
     return {
diff --git a/tests/components/zwave_js/test_diagnostics.py b/tests/components/zwave_js/test_diagnostics.py
index e7d7d9594bd..aa5ec77b798 100644
--- a/tests/components/zwave_js/test_diagnostics.py
+++ b/tests/components/zwave_js/test_diagnostics.py
@@ -18,11 +18,11 @@ from homeassistant.components.zwave_js.helpers import (
     get_value_id_from_unique_id,
 )
 from homeassistant.core import HomeAssistant
-from homeassistant.helpers.device_registry import async_get as async_get_dev_reg
-from homeassistant.helpers.entity_registry import async_get as async_get_ent_reg
+from homeassistant.helpers import device_registry as dr, entity_registry as er
 
 from .common import PROPERTY_ULTRAVIOLET
 
+from tests.common import MockConfigEntry
 from tests.components.diagnostics import (
     get_diagnostics_for_config_entry,
     get_diagnostics_for_device,
@@ -57,10 +57,26 @@ async def test_device_diagnostics(
     version_state,
 ) -> None:
     """Test the device level diagnostics data dump."""
-    dev_reg = async_get_dev_reg(hass)
+    dev_reg = dr.async_get(hass)
     device = dev_reg.async_get_device({get_device_id(client.driver, multisensor_6)})
     assert device
 
+    # Create mock config entry for fake entity
+    mock_config_entry = MockConfigEntry(domain="test_integration")
+    mock_config_entry.add_to_hass(hass)
+
+    # Add an entity entry to the device that is not part of this config entry
+    ent_reg = er.async_get(hass)
+    ent_reg.async_get_or_create(
+        "test",
+        "test_integration",
+        "test_unique_id",
+        suggested_object_id="unrelated_entity",
+        config_entry=mock_config_entry,
+        device_id=device.id,
+    )
+    assert ent_reg.async_get("test.unrelated_entity")
+
     # Update a value and ensure it is reflected in the node state
     event = Event(
         type="value updated",
@@ -92,16 +108,27 @@ async def test_device_diagnostics(
     }
     # Assert that we only have the entities that were discovered for this device
     # Entities that are created outside of discovery (e.g. node status sensor and
-    # ping button) should not be in dump.
+    # ping button) as well as helper entities created from other integrations should
+    # not be in dump.
     assert len(diagnostics_data["entities"]) == len(
         list(async_discover_node_values(multisensor_6, device, {device.id: set()}))
     )
+    assert any(
+        entity.entity_id == "test.unrelated_entity"
+        for entity in er.async_entries_for_device(ent_reg, device.id)
+    )
+    # Explicitly check that the entity that is not part of this config entry is not
+    # in the dump.
+    assert not any(
+        entity["entity_id"] == "test.unrelated_entity"
+        for entity in diagnostics_data["entities"]
+    )
     assert diagnostics_data["state"] == multisensor_6.data
 
 
 async def test_device_diagnostics_error(hass: HomeAssistant, integration) -> None:
     """Test the device diagnostics raises exception when an invalid device is used."""
-    dev_reg = async_get_dev_reg(hass)
+    dev_reg = dr.async_get(hass)
     device = dev_reg.async_get_or_create(
         config_entry_id=integration.entry_id, identifiers={("test", "test")}
     )
@@ -123,12 +150,12 @@ async def test_device_diagnostics_missing_primary_value(
     hass_client: ClientSessionGenerator,
 ) -> None:
     """Test that device diagnostics handles an entity with a missing primary value."""
-    dev_reg = async_get_dev_reg(hass)
+    dev_reg = dr.async_get(hass)
     device = dev_reg.async_get_device({get_device_id(client.driver, multisensor_6)})
     assert device
 
     entity_id = "sensor.multisensor_6_air_temperature"
-    ent_reg = async_get_ent_reg(hass)
+    ent_reg = er.async_get(hass)
     entry = ent_reg.async_get(entity_id)
 
     # check that the primary value for the entity exists in the diagnostics
@@ -212,7 +239,7 @@ async def test_device_diagnostics_secret_value(
     client.driver.controller.nodes[node.node_id] = node
     client.driver.controller.emit("node added", {"node": node})
     await hass.async_block_till_done()
-    dev_reg = async_get_dev_reg(hass)
+    dev_reg = dr.async_get(hass)
     device = dev_reg.async_get_device({get_device_id(client.driver, node)})
     assert device