Heterojunction diodes consisting of n-type vertically aligned ZnO nanowire core by hydrothermal growth and p-type ZnTe film shell by magnetron sputtering were prepared on fluorine-doped tin oxide (FTO) glass substrates. The diodes were characterized by scanning electron microscope, transmission electron microscope, X-ray diffraction pattern, and UV-vis absorption spectra. Diode rectifying behavior was observed in the current–voltage characteristics. The enhanced photocurrent under illumination suggests the efficicent separation of photogenerated carrier within the heterojunction. The results indicate that the ZnO/ZnTe core/shell structures can be made into useful photovoltaic devices.