The nano ZnO/Pd particles with the crystallite size about 41-46 nm were synthesized by hydrothermal method and ethanol-assisted hydrothermal method with Zn²⁺and Pd²⁺molar ratio of 100:0.5, 100:1, 100:2.The samples of ZnO/Pd were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive X-ray spectrometry(EDS), ultraviolet-visible spectroscopy(UV-vis) and were used in the photocatalysis of unsymnetrical dimethylhydrazine(UDMH) wastewater under UV-light and sun light.Results show that the UV absorbtion property is extremely expanded by doping Pd, and ranged to 400-800 nm in visible light district.The maximum degradation rate of ZnO/Pd in sunlight is 80.5% and under UV-light is 76.8% in 2 h.The variation of the photocatalytic middle-product under different light sources was analyzed at last.It is found that the middle-product is decomposed more quickly and throughly under sunlight, with COD degradation rate of 75.7%, which is better than UV-light of 58.2%.