Aim:  The aim of the present study was to identify influencing factors for sexual violence in sexually experienced teenage girls. Methods:  Eighty sexually experienced teenage girls aged between 14 and 19 attending obstetrics and gynecology clinics in suburban Tokyo were selected as subjects. After completing a simple questionnaire on sexual behavior and lifestyle the subjects were interviewed using a semistructured interview technique. Logistic regression analysis was used to identify factors associated with sexual violence. Results:  Police and government statistics for rape, sexual and domestic violence in Japan are extremely low. However, the present study showed that 52.5% of subjects had been victims of sexual violence. Furthermore, of these, 69.0% had been forced to have sex with a partner and 64.3% had been raped by someone other than a partner. Factors influencing the risk of sexual violence were sexual behavior and attitudes towards sexuality and lifestyle. Having a sexually transmitted infection was not an influencing factor. Conclusions:  It is important to identify teenage girls attending obstetrics and gynecology clinics at risk of sexual violence and to teach them about the risks of sexual behavior associated with imbalances of power. Furthermore, it is essential to support victims of sexual violence to protect them from the recurrence of such abuse. (Reprod Med Biol 2008; 7: 181-187).