Substantial effort has been devoted to synthesizing plasmonic metal/semiconductor heteronanostructures with controlled morphology owing to their excellent performance ranging from photocatalysis to optical information processing. However, growing semiconductor heterojunctions with both counterparts in direct contact with the plasmonic metal nanostructures remains challenging. Herein, we report a three-step method to grow CdS–Cu_2−xS lateral heteroshells on Au nanoparticles with all components directly connected with each other. Ag₂S semi shells are initially grown on the Au nanoparticles as an interim layer, Cu_2−xS semi shells are then grown on the uncovered surface of the Au nanoparticles, and CdS is generated by replacing Ag₂S and the Au core complex with CdS–Cu_2−xS lateral heteroshells Au/CdS–Cu_2−xS is finally obtained. These complexes integrate the plasmon resonances of Au in the visible region and that of Cu_2−xS in the near-infrared region, and therefore show improved photocatalytic activity and high photothermal efficiency. This study offers a synthetic approach to grow metal sulfides on Au nanostructures which have diverse applications in photocatalysis and photothermal therapy.