diff --git a/homeassistant/components/synology_dsm/config_flow.py b/homeassistant/components/synology_dsm/config_flow.py
index c1e8cf553d9..025b2959026 100644
--- a/homeassistant/components/synology_dsm/config_flow.py
+++ b/homeassistant/components/synology_dsm/config_flow.py
@@ -133,7 +133,7 @@ class SynologyDSMFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
             return await self._show_setup_form(user_input, errors)
 
         # Check if already configured
-        await self.async_set_unique_id(serial)
+        await self.async_set_unique_id(serial, raise_on_progress=False)
         self._abort_if_unique_id_configured()
 
         config_data = {
@@ -162,6 +162,13 @@ class SynologyDSMFlowHandler(config_entries.ConfigFlow, domain=DOMAIN):
         if self._host_already_configured(parsed_url.hostname):
             return self.async_abort(reason="already_configured")
 
+        if ssdp.ATTR_UPNP_SERIAL in discovery_info:
+            # Synology can broadcast on multiple IP addresses
+            await self.async_set_unique_id(
+                discovery_info[ssdp.ATTR_UPNP_SERIAL].upper()
+            )
+            self._abort_if_unique_id_configured()
+
         self.discovered_conf = {
             CONF_NAME: friendly_name,
             CONF_HOST: parsed_url.hostname,
diff --git a/tests/components/synology_dsm/test_config_flow.py b/tests/components/synology_dsm/test_config_flow.py
index 9a9283256c5..66f752ffaf4 100644
--- a/tests/components/synology_dsm/test_config_flow.py
+++ b/tests/components/synology_dsm/test_config_flow.py
@@ -321,6 +321,30 @@ async def test_missing_data_after_login(
     assert result["errors"] == {"base": "missing_data"}
 
 
+async def test_form_ssdp_already_configured(
+    hass: HomeAssistantType, service: MagicMock
+):
+    """Test ssdp abort when the serial number is already configured."""
+    await setup.async_setup_component(hass, "persistent_notification", {})
+
+    MockConfigEntry(
+        domain=DOMAIN,
+        data={CONF_HOST: HOST, CONF_USERNAME: USERNAME, CONF_PASSWORD: PASSWORD},
+        unique_id=SERIAL.upper(),
+    ).add_to_hass(hass)
+
+    result = await hass.config_entries.flow.async_init(
+        DOMAIN,
+        context={"source": SOURCE_SSDP},
+        data={
+            ssdp.ATTR_SSDP_LOCATION: "http://192.168.1.5:5000",
+            ssdp.ATTR_UPNP_FRIENDLY_NAME: "mydsm",
+            ssdp.ATTR_UPNP_SERIAL: SERIAL,
+        },
+    )
+    assert result["type"] == data_entry_flow.RESULT_TYPE_ABORT
+
+
 async def test_form_ssdp(hass: HomeAssistantType, service: MagicMock):
     """Test we can setup from ssdp."""
     await setup.async_setup_component(hass, "persistent_notification", {})
@@ -331,6 +355,7 @@ async def test_form_ssdp(hass: HomeAssistantType, service: MagicMock):
         data={
             ssdp.ATTR_SSDP_LOCATION: "http://192.168.1.5:5000",
             ssdp.ATTR_UPNP_FRIENDLY_NAME: "mydsm",
+            ssdp.ATTR_UPNP_SERIAL: SERIAL,
         },
     )
     assert result["type"] == data_entry_flow.RESULT_TYPE_FORM