Abstract: Objective To explore the changing trend of hepatitis C virus (HCV) prevalence and risk factors among new entrants in community-based methadone maintenance treatment (MMT). Methods Totally 8 830 new entrants in MMT of Guangdong province were included in this study. HCV infection rates were calculated and logistic regression model was conducted to analyse related risk factors in different years. Results 4 485 new entrants in MMT were recruited from 2006 to 2008 and the prevalence of HCV infection was 77.1%; 3 028 new entrants in MMT were recruited from 2009 to 2011 and the prevalence of HCV infection was 80.7%; 1 317 new entrants in MMT were recruited from 2012 to 2014 and the prevalence of HCV infection was 77.0%; Trend χ² test was not statistical significant(χ_trend²=1.72,P=0.189). Multivariate Logistic regression analysis showed that in 2006-2008, higher education level and being married were protective for HCV infection (all P<0.05), whereas long history of drug use, closer ties with drug fellows in the past six months and injecting drug use were risk factors for HCV infection (all P<0.05). In 2009-2011, higher education level and being married were protective for HCV infection (all P<0.05), however, long history of drug use,closer ties with drug fellows in the past six months and injecting drug use were risk factors for HCV infection (all P<0.05). In 2012-2014, female, long history of drug use and injecting drug use were risk factors for HCV infection (all P<0.05). Conclusions The prevalence of HCV infection among MMT new entrants was high and had no downtrend. The risk factors were changing, however, long history of drug use and injecting drug use were continuous risk factors for HCV infection. More intervention should be given to publicity of MMT to strengthen prevention and treatment of HCV.