Self-powered photodetectors based on nanomaterials have attracted lots of attention for several years due to their various advantages. In this paper, we report a high performance Cu2O/ZnO self-powered photodetector fabricated by using electrochemical deposition. ZnO nanowires arrays grown on indium-tin-oxide glass are immersed in Cu2O film to construct type-II band structure. The Cu2O/ZnO photodetector exhibits a responsivity of 0.288 mA/W at 596 nm without bias. Compared with Cu2O photoconductive detector, the responsivity of the Cu2O/ZnO self-powered photodetector is enhanced by about two times at 2 V bias. It is attributed to the high power conversion efficiency and the efficient separation of the photogenerated electron–hole pairs, which are provided by the heterojunction. The outstanding comprehensive performances make the Cu2O film/ZnO nanowires self-powered photodetector have great potential applications.