Abstract Background The prevalence of unprotected anal intercourse (UAI) is high among Chinese men who have sex with men (MSM). As important aspects of quality of life (QOL), psychological health and social relationships have been found to be associated with UAI among MSM, which was of great concern for intervening on UAI. Methods We conducted a cross-sectional study in Zhengzhou, Henan province, and in Huludao, Liaoning province, China, to measure quality of life (QOL) using the brief version of the World Health Organization Quality of Life (WHOQOL-BREF). Cronbach's α coefficient was used to test the internal consistency of the questionnaire items, and construction validity was assessed by exploratory factor analysis. T-test, chi-square test and multivariate logistic analysis were carried out to test the relationship between quality of life and unprotected anal intercourse. Results The questionnaires of 320 of the 373 men who have sex with men that were surveyed met our validity criteria (response rate: 85.8 %). A total of 161 subjects (50.3 %) reported having unprotected anal sex in the last 6 months. The results of univariate analysis indicated that having unprotected anal sex was significantly associated with psychological health (PSYCH), social relationships (SOCIL), age, and marital status (P-value