Background: Sexual compulsivity and its relationship with unprotected intercourse have long been an intriguing topic, but its existential meaning in the management of public health or, more precisely, STIs (sexually transmitted infections) has rarely been studied to date. This study examines whether sexual compulsivity plays a role in unprotected intercourse among STI patients and its variation regarding gender and different types of sexual partner.Method: We carried out a cross-sectional study using mixed methods including a survey of 302 men and 362 women. Two clinics were purposely chosen for the study. Data were analyzed using IBM SPSS for Windows.Results: The ages of the 664 participants ranged from 18 to 76 years, with more than half (58.73%) 26–40 years old. Of these 664 participants, 449 (157 male and 237 female) reported having unprotected intercourse during the past 6 months. Almost one-quarter of the male participants scored high on the Sexual Compulsivity Scale, compared with only 4.4% of females. Although the only statistically significant difference (p<0.01) was in relation to unprotected intercourse with a casual sexual partner, the difference between male/female and regular/casual sexual partners remained evident.Conclusions: Sexual compulsivity is evidently a potential predictor of unprotected intercourse with a casual sexual partner in male STI patients, while the use of condoms is more likely to be affected by other factors. In addition to general sexual education, counseling interventions should be provided by related health institutions, and specific intervention methods targeting each gender and different behavioral types should be considered.