In this communication we present the integration of graphene on the top electrode of solidly mounted resonators based on piezoelectric AlN thin films for gravimetric sensor applications. Because its particular chemical structure, graphene shows great potential as a bio-functionalization platform. However, in order to be commercially viable, direct deposition on the resonators is preferred to transfer techniques. The high temperatures involved in graphene chemical vapor deposition make this integration complex. Specially developed acoustic resonators, which can withstand high temperatures, combined with the use of multi-layered top electrodes for AlN resonators, allow a successful integration of graphene. Finally, oxygen plasma treatments to optimize the creation of defects on the graphene layer can be used to firmly bond receptors on its surface.