We demonstrate the design of the recyclable photocatalyst based on ferromagnetic (FM) ZnO- TiO2 core-shell nanowires (NWs). Since the band gaps and band edge energies of bulk ZnO and anatase TiO2 are equal to each other within about 45mV, TiO2 and ZnO can form an p-p+ heterojunction free of band discontinuities and with a built-in potential. The resulting radial field will increase hole density in the TiO2 layer while reduce hole concentration at the interface between the core and the shell, which in turn will decrease the rate of recombination in the photocatalytic TiO2, and hence increase the efficiency of photocatalyst. On the other hand, the NWs with FM cores can be easily collected and refreshed using solenoid and suitable for the recyclable usage of the NW catalyst