In order to know the microbial contamination condition of sewage discharges,the total bacterial count and colibacillary of five typical sewages are determined in Zhenjiang city.The five places are respectively situated in two network inspection wells of Dashikou and Qinyunmen、 two overflow mouth Liming,he and Zhongshanqiao and Jiangbing pumping station.The results show that,geometric mean of total bacterial count is 6.36×105cfu/mL and fluctuating scope is 4.32×104~ 4.37×107 cfu/mL; geometric mean of general colibacillary population is 6.36×105 cfu/mL and fluctuating scope is 4.32×104 ~ 4.37×107cfu/mL.The distinction of mean total bacterial count in five types sewage is big,however,the highest is in residential areas.At the same time,the general colibacillary population is different in different places.The results indicate that bacterial contamination strength in sewage of Zhenjiang areas is rather serious and three places are serious superstandard.