Objective: To study the effects of educational background of men who have sex with men (MSM) on their high risk sexual behaviors and the HIV/STI infection rates., Methods: During July to November of 2009 and March to October of 2010, snowball and convenience sampling methods were adopted to recruit MSM from MSM venues and via the internet in Changzhou city of Jiangsu province, and finally 659 MSM were conducted a questionnaire survey and serological testing. According to the educational background of MSM, they were divided into 3 groups, that is, junior high school group (206 cases), high school group (254 cases), and university group (199 cases). The questionnaire mainly includes information on social demography, sexual behaviors, condom use, etc. Blood samples were collected for HIV and syphilis spirochete detection, and urine samples were also collected in 291 MSM who were recruited during July to November of 2009 for neisseria gonorrhoeae and chlamydia trachomatis nucleic acid detection. χ(2) test and other statistical analysis methods were used to compare the characteristics of sexual behaviors and HIV/STI infections in 3 groups., Results: Of the 659 valid questionnaires returned, junior high school group, high school group, and university group accounted for 31.3% (206 cases), 38.5% (254 cases) and 30.2% (199 cases). Places where MSM of different education levels most often to seek sexual partners, were significantly different. Junior high school group and high school group mostly went to bath house/sauna club (56.3%, 116 cases) and bar (34.8%, 88 cases) for partners, respectively, while the university group sought partners mainly through the internet (41.1%, 81 cases) (χ(2) = 99.35, P < 0.05). 53.4% (109/204) of the junior high school group had anal sex with men in the last 6 months, which was higher than that of high school group (67.7%, 172/254) (χ(2) = 9.74, P < 0.05) and university group (72.7%, 144/198) (χ(2) = 16.04, P < 0.05) . A total of 54.4% (111/204) of the junior high school group had sex with women in the last 6 months, which was higher than that of university group (38.6%, 76/197) (χ(2) = 10.10, P < 0.05) , but was not statistically significantly different from that of high school group (46.9%, 119/254) (χ(2) = 2.59, P = 0.11) . The rates of condom use with men at the last anal sex in junior high school group (73.4%, 80/109) , high school group (78.0%, 131/168) and university group (73.9%, 105/142) were similar. The rates of condom use with women in the last intercourse in junior high school group, high school group and university group were 51.8% (57/110), 54.6% (65/119) and 61.8% (47/76), respectively(χ(2) = 1.88, P = 0.39) . In junior high school group, high school group and university group, the infection rates of HIV were 9.2% (19/206), 10.6% (27/254) and 5.6% (11/197) (χ(2) = 3.68, P = 0.16), the positive rates of neisseria gonorrhoeae were 3.8% (3/79), 3.4% (4/117) and 0.0% (0/95) (χ(2) = 3.85, P = 0.14), the positive rates of chlamydia trachomatis were 5.1% (4/79), 9.4% (11/117) and 4.2% (4/95) (χ(2) = 2.70, P = 0.26). The infection rate of syphilis in junior high school group was 19.9% (41/206), which was higher than high school group (12.2%, 31/254) (χ(2) = 5.11, P < 0.05) and university group (10.2%, 20/197) (χ(2) = 7.45, P < 0.05 )., Conclusion: There was no obvious correlation between education level and high risk sexual behaviors;MSM with lower education level were at higher risk of infection of syphilis.