Abstract: Objective To investigate the prevalence of HIV and risk factors among drug users in detoxification centers in Xi'an.Methods The drug users in detoxification centers in Xi'an were interviewed by trained health workers and their blood samples were collected.Results Among 2267 participants.HIV prevalence was 1.9%.Multivariate logistic regression analysis shewed that IDUs who shared injecfion equipment with others.The minority(Yi or Uigers)were associated with HIV infection.OR is 1.58,2.58 and 17.91 respectively.(95%CI is 1.05～2.11、1.42～3.74 and 13.2-22.62).The HIV infecfion rate is slightly higher in drug users who have sexand sexwith casual partners than who haven't,with the percentage of 2.2% and 3.0% respectively.Conclusion The HIV prevalence was low in drug users in detoxification centers in Xi'an,but there were risk behaviors related to HIV infection.