Metal　nanocluster　(NC)-mediated　photocatalytic　CO2　conversion　is　an　emerging　avenue　for　achieving　carbon　neutrality,　yet　it　remains　underexplored　due　to　the　ultrashort　charge　lifespan　of　metal　NCs.　To　surmount　this　obstacle,　metal　NC/transition　metal　chalcogenide　(TMC)　heterostructures　are　constructed　via　a　ligand-initiated　electrostatic　self-assembly　buildup.　In　this　meticulously　designed　nanoarchitecture,　glutathione　(GSH)-protected　metal　NCs　[Au　x　@GSH,　Au22(GSH)18,　Ag9(GSH)6,　Ag16(GSH)9,　Ag31(GSH)19]　are　uniformly　anchored　on　the　two-dimensional　(2D)　TMC　(CdS,　ZnIn2S4,　CdIn2S4,　In2S3)　framework,　leading　to　well-defined　metal　NC/TMC　composite　photosystems.　The　favorable　energy　level　alignment　between　these　metal　NCs　and　TMCs　synergistically　endows　metal　NC/TMC　heterostructures　with　markedly　increased　photoredox　activities,　encompassing　photocatalytic　CO2　reduction,　H2　production,　and　aromatic　alcohol　oxidation　under　visible　light,　far　surpassing　the　corresponding　pristine　TMC　counterparts.　Alloy　NCs　(Au　x　Ag1-x　,　Au　x　Cu1-x　)/TMCs　are　also　constructed　to　demonstrate　the　universality　of　the　heterostructures.　The　generation　of　a　type　II　charge　transport　pathway　between　metal　NCs　and　TMCs　is　unveiled　to　account　for　the　photoredox　mechanisms.　Our　work　will　provide　an　interesting　idea　for　tuning　charge　transfer　over　metal　NCs　for　photocatalysis.