Objective: To investigate the awareness of acquired immune deficiency syndrome (AIDS) knowledge and AIDS-related behaviors among youth students in gay dating sites, and to provide evidences for AIDS prevention education through the internet.Methods: The students in gay dating sites, selected by a snowball sampling, were interviewed by questionnaires.Chi-square tests were used to analyze the awareness of AIDS knowledge among the students of different characteristics.The Logistic regression was used to analyze the factors associated with ever testing for HIV.Results: In the study, 469 youth students in gay dating sites filled in the questionnaires, and a total of 442 (94.2%) valid samples were collected.The awareness of HIV/AIDS knowledge for the public among the youth students in gay dating sites was 83.9% (371).The awareness of HIV/AIDS knowledge for the youth students was 77.1% (341), and the rate of ever testing for HIV was 52.0% (230).The awareness of HIV/AIDS knowledge for the public in the students were different in different age groups (P=0.001), different marital statuses (P<0.001), different sexual orientations (P<0.001), and different genders of the first sexual partner (P<0.001).The awareness of HIV/AIDS knowledge for the youth students were different in different age groups (P=0.010), different marital status (P=0.004), different sexual orientations (P<0.001), and different genders of the first sexual partner (P<0.001).The rate of ever having sexual intercourse among the youth students in gay dating sites was 75.1% (332), and the rate of multiple sexual partnerships among the youth students was 41.3% (137).Compared with homosexual orientation, sexual orientation as heterosexual (OR=0.282,95%CI:0.151 to 0.528) and not sure (OR=0.175,95%CI: 0.035 to 0.885) were risk factors of ever testing for HIV.Multiple sexual partnerships (OR=2.103,95%CI:1.278 to 3.462) were promoting factors of ever testing for HIV.Conclusion: The rate of high-risk behaviors among the youth students in gay dating sites was high.The concern should be raised to heterosexual male students who had tendency to homosexual behavior.The AIDS prevention education should be developed in gay dating sites, to improve the self-protection awareness of the youth students.