Three coordination polymers (CPs) with square-planar Cu-II/Ni-4(II) subunits were formed in one step by subcomponent self-assembly, giving rise to an unprecedented linking, variety of in situ embedded metalloligands and Cul clusters. All CPs exhibit unusual visible-light adsorption. Enhanced photocatalytic activity and high selectivity were observed in the oxidation of benzene under visible-light irradiation.