Cell-free　networks　and　reconfigurable　intelligent　surfaces　(RIS)　are　two　promising　techniques　for　future　wireless　communications.　The　integration　of　RIS　into　cell-free　networks,　termed　RIS-aided　cell-free　networks,　offers　the　potential　to　significantly　enhance　network　performance.　However,　the　realization　of　this　potential　is　constrained　by　the　limited　capacities　of　the　fronthaul　links.　To　address　this　challenge,　we　investigate　the　joint　design　of　access　point　(AP)　clustering,　transmit　and　passive　beamforming　in　RIS-aided　cell-free　networks.　The　objective　is　to　maximize　the　weighted　sum-rate　performance　while　minimizing　the　number　of　clustered　APs　to　alleviate　the　fronthaul　overhead.　The　problem　is　formulated　in　a　group　sparse　manner,　employing　a　mixed　zero-norm/two-norm　term　to　represent　the　number　of　the　clustered　APs.　To　solve　this　problem,　we　first　approximate　the　mixed　zero-norm/two-norm　term　by　the　mixed　one-norm/two-norm　term　and　provide　its　equivalent　formulation　by　introducing　receive　beamforming　vectors　and　weight　parameters.　Then,　an　iterative　method　is　proposed　based　on　the　block　coordinate　descent　(BCD)　technique,　which　is　guaranteed　to　converge　to　a　stationary　point.　Simulation　results　demonstrate　the　effectiveness　of　the　proposed　method.　©　1967-2012　IEEE.