Abstract： Objective To identify factors predicting serological response in patients after syphilis treatment.Methods A retrospective study was performed on 226 human immunodeficiency virus (HIV)-negative patients with syphilis.Serological response was evaluated in these patients within one year after regular treatment of syphilis.A multivariate logistic regression analysis was conducted to identify possible factors associated with serological response,such as age,clinical stage,gender,initial rapid plasma regain (RPR) titer,administered drugs,and so on.Results One year after the recommended therapy,152 out of the 226 patients achieved a serological cure,and 73 (32.4％) remained in the serofast state.The serofast rate increased with clinical course.The multivariate logistic regression analysis indicated that female patients (OR =2.517,95％ CI:1.159-5.464),non-penicillin treatment (OR =4.959,95％ CI:1.650-14.901) and a baseline RPR titer ≤ 1:16 (OR =4.370,95％ CI:1.311-14.562) were associated with a higher serofast rate,while primary or secondary syphilis as well as young patients aged 25 years or less were associated with an increased likelihood of a serological cure (both P ＜ 0.05).Conclusion The serological response in patients after syphilis treatment is associated with clinical stage,gender,age,baseline RPR titer,and administered drugs.