Herein, we have synthesized successfully a three-dimensional/two dimensional (3D/2D) core-shell Cu2O@Fe-Ni3S2 nanoflower on copper foam at room temperature. Remarkably, by virtue of rich active sites and vacancies, large surface area, high conductivity and close contact with the electrolyte, the Cu2O@Fe-Ni3S2 catalyst exhibits superior stability and oxygen evolution reaction performance.