Objective To evaluate the long-term effectiveness of the first set 8 methadone maintenance treatment (MMT) clinics in China. Methods Repeated cross-sectional surveys were conducted on the first month after the enrollment and 5 years later,among drug users who received MMT,using a standard questionnaire.Data on demographic characteristics,HIV-related high-risk bchaviors,criminal records associatcd with drug use and related family/social functions were collected and analyzed.Results There were 252 and 195 participants being interviewed at the baseline and the 5-year surveys,respectively,.Of them,66 participants were involved in both surveys.There was no significant differences on factors as ethnicity,level of education,working status,marital status and living status (P＞0.05) between the baselinc and the 5-year surveys.Compared with data from the baseline survey,participants' behavior on drug abuse (100.0％ vs.24.1％,P＜0.001 ),needle sharing behavior ( 19.4％ vs.0.0％,P ＜ 0.001 ),and exchanging sex for drugs ( 34.5 ％ vs.0.0％,P＜0.001 ) had significant decreases at the 5-year survey.Rates on condom use ( 10.6％ vs.25.0％,P=0.004),and having jobs (27.8％ vs.47.7％,P＜0.001 ) had been improved significantly,while self-reported criminal cases related to drug use (15.1％ vs.1.5％,P＜0.001) and the contacts with drug users (88.9％ vs.31.3％,P＜0.001) had been significantly reduced after joining the MMT program.Conclusion MMT could play an active role in reducing the HIV-related high-risk behaviors,criminal cases associated with drug abuse as well as enhancing the family and social functions of the MMT patients.Providing high quality service to the MMT clinic and trying to keep the drug users stick to the program remain difficult.It was also important to improve the training programs for staff working at the MMT clinics.