Odor gas ejected during urban sewage treatment can not only weaken the renewability of wastewater, but also endanger the human health. It is mainly composed of ammonia nitrogen and sulfide. This paper aims to shed new light on the odor elimination for the sewage treatment plant based on photocatalytic oxidation method. The findings show that WO3 or TiO2, if used alone, has a higher degradation activity for sulfides. Under the condition of visible light shines, the catalytic performance of WO3 is higher than that of TiO2; TiO2/WO3 system doped with WO3 can improve the photocatalytic activity. As the dose of TiO2 continues to rise, the photocatalytic activity of ammonia nitrogen and sulfide can be enhanced; but when it increases to a certain extent, the degradation of organic pollutants is on the decline. According to different contents of TiO2 and WO3, the sewage odor is treated by three sets of catalysts. After the test, It is found that the catalyst 2 (WO3: TiO2, 3.2:1) removes inorganic pollutants significantly better than other two sets.