The quality of life (QOL) of men who have sex with men (MSM) has received increasing attention in recent years. Our study surveyed the QOL and explored the influence of social support on QOL in Chinese MSM. A cross-sectional survey was conducted from September 2013 to March 2014 of 438 MSM in Huludao and Zhengzhou City, China. The results of univariate analysis showed that higher QOL scores were associated with receiving psychosocial counseling, higher health education, younger age and marital status of being single or unmarried p < 0.05). The structural equation model fitted well, with χ2 = 2083.47 (p < 0.05), RMSEA = 0.07, and GFI = 0.88. Among the latent factors, social support, with a factor load of 0.47, had greater impact on QOL than demographic characteristics. Within social support, the item loads for psychosocial counseling and health education were 0.17 and 0.29, respectively. Basic demographic characteristics also influenced social support, with a factor load of -0.65. For demographic characteristics, the greatest item loads were for marital status and age (0.77 and 0.71, respectively). These findings suggest that strengthening social support, especially for older and married individuals, would improve QOL in MSM in China.