In recent years, there has been a significant increase in the use of gay mobile phone applications (gay apps) and HIV prevalence among men who have sex with men (MSM) in China. The aim of this study was to investigate whether there was a relationship between the use of gay apps and HIV infection and provide a targeted intervention to MSM. A cross-sectional study was conducted. Chinese MSM who were over 18 years old and had self-reported homosexual intercourse in the past six months were interviewed in 2016. Proportions were used for categorical variables and determinants of HIV infection were assessed using univariate and multivariate regression. Of the 403 participants, nearly 66.0% reported having used gay apps to seek sexual partners in the past six months. A higher proportion of the gay app users were younger than 19 years old, single, had high school education, were earning less than 115 GBP income per month, and identified themselves as homosexual. Compared to app non-users, a greater proportion of app users reported a higher frequency of male-male sexual contact (≥1 time/week: 57.5% versus 39.4%, p < 0.01), multiple male sex partners (34.2% versus 11.7%, p < 0.001), and unprotected sex with men (51.5% versus 36.5%, p < 0.01) in the past six months. The prevalence of HIV among app users was 7.9%. HIV infection was significantly associated with being an app user (adjusted odds ratio = 5.2, 95% CI = 1.1-24.3). It is suggested that the use of gay apps, especially Blued, is popular among Chinese MSM and is associated with high-risk sexual behaviors and HIV infection. Therefore, there is an urgent need to promote HIV testing and HIV prevention through gay apps to decrease the risk of HIV infection among Chinese MSM.