The chemoselective hydrogenation of structurally diverse nitroaromatics is a challenging process. Generally, catalyst activity tends to decrease when excellent selectivity is guaranteed. We here present a novel photocatalyst combining amino-functionalized carbon dots (N-CDs) with copper selenite nanoparticles (N-CDs@CuSeO3) for simultaneously improving selectivity and activity. Under visible light irradiation, the prepared N-CDs@CuSeO3 exhibits 100% catalytic selectivity for the formation of 4-aminostyrene at full conversion of 4-nitrostyrene in aqueous solvent within a few minutes. Such excellent photocatalytic performance is mainly attributed to the precise control of the hydrogen species released from the ammonia borane by means of light-converted electrons upon N-CDs@CuSeO3. Besides, the defect states at the interface of N-CDs and CuSeO3 enable holes to be trapped for promoting separation and transfer of photogenerated charges, allowing more hydrogen species to participate in catalytic reaction.