Abstract: Objective To assess the levels of disinfectant by-products in centralized drinking water in a rural region of southern Chian and to provide basic information for the control of disinfectant by-products in rural water supply facilities.Methods A total of 15 rural centralized water supply facilities were selected in a southern region and some parameters of disinfectant by-products in the samples of raw water,filtered water and product water were detected.The water sample collection,storage and detection were conducted according to "National Standard Examinations for Drinking Water"(GB/T5750-2006).Results The contents of chlorate(1.59 mg/L) and trihalomethane(1.133 mg/L) in 2 of 15 water samples did not meet the standard requirement.The contents of trihalomethane and halocetic acid were similar for water samples from water supply facilities using chlorination disinfection and chloramine disinfection,but the contents were lower for water samples with chloramine disinfection.Chlorate and chlorite were mainly detected in water samples with chlorine dioxide disinfection.Conclusion The contents of chlorate and trihalomethane exceeding national standard are detected in water samples from centralized water supply facilities in rural areas of southern China.