Aiming at the problems on high toxic and hard degradable intermediates existing in unsymmetrical dimethylhydrazine (UDMH) degradation method at present, a detection method of ultraviolet(UV) spectroscopy to trace and analyze the oxidative degradation products of UDMH wastewater was established. The assignation of product peaks in UDMH wastewater degradation process was determined. The degradation products of two oxidation systems Cu²⁺/H₂O₂ system and Fenton system were analyzed. The degradation mechanism was deduced. Results show that the UV peaks of UDMH and unsymhydrazone(FDMH) are at 200 nm and 235 nm, respectively. Two systems can effectively degrade UDMH wastewater, but Cu²⁺/H₂O₂ system has more intermediate products and higher toxicity. The addition of H₂O₂ before adding Cu²⁺can reduce intermediates. The addition of iron powder is beneficial to decrease intermediates. Fenton system can effectively inhibit the producing of toxic intermediate products.