diff --git a/dlls/iphlpapi/iphlpapi.spec b/dlls/iphlpapi/iphlpapi.spec
index 228f64f955b..d7a52b7e4c5 100644
--- a/dlls/iphlpapi/iphlpapi.spec
+++ b/dlls/iphlpapi/iphlpapi.spec
@@ -15,7 +15,7 @@
 #@ stub ConvertInterfaceGuidToLuid
 #@ stub ConvertInterfaceIndexToLuid
 #@ stub ConvertInterfaceLuidToAlias
-#@ stub ConvertInterfaceLuidToGuid
+@ stdcall ConvertInterfaceLuidToGuid( ptr ptr )
 #@ stub ConvertInterfaceLuidToIndex
 #@ stub ConvertInterfaceLuidToNameA
 #@ stub ConvertInterfaceLuidToNameW
diff --git a/dlls/iphlpapi/iphlpapi_main.c b/dlls/iphlpapi/iphlpapi_main.c
index 3eaefab119b..69ebca26dd6 100644
--- a/dlls/iphlpapi/iphlpapi_main.c
+++ b/dlls/iphlpapi/iphlpapi_main.c
@@ -2658,3 +2658,12 @@ ULONG WINAPI GetTcp6Table2(PMIB_TCP6TABLE2 table, PULONG size, BOOL order)
     FIXME("pTcp6Table2 %p, size %p, order %d: stub\n", table, size, order);
     return ERROR_NOT_SUPPORTED;
 }
+
+/******************************************************************
+ *    ConvertInterfaceLuidToGuid (IPHLPAPI.@)
+ */
+DWORD WINAPI ConvertInterfaceLuidToGuid(const NET_LUID *luid, GUID *guid)
+{
+    FIXME("(%p %p) stub\n", luid, guid);
+    return ERROR_CALL_NOT_IMPLEMENTED;
+}