Abstract: Objective To evaluate the efficacy of initial methadone maintenance treatment(MMT)at community clinics in Guangdong province.Methods Adynamic follow-up investigation was carried out in 445 patients who underwent the initial MMT in Guangdong province since January 2006 to March 2008 and the effec tiveness of the maintenance treatment was analyzed.Results During the follow-up period,62.79% of participants dropped out from the treatment.Nonscheduled urine morphine tests showed a positive rate of 34.02% after one month and 35.00% after one year.The longer the treatment time was,the higher the patientsp life quality was.More than 80.00% of the participants gained knowledge about AIDS prevention after treatment.No new HIV in fected patients were reported am ong rem a ining participants.More than 80.00% of the participants achieved improvement in social-family function compared with the baseline data(30.34%).Crmie rate decreased substantially from 30.34% to 1.57%(P<0.001).Conclusion MMT played an active role in reducing drug use,restraining HIV/AIDS transmission,improving drug-usersp life quality,restoring social-family function and reducing crmie.