The phenomenon of male sexual victims becoming sexual perpetrators is called the sexual victim-perpetrator cycle. Reviewing past research investigating the causal mechanisms behind the sexual victim-perpetrator cycle, it was found that a theoretical proposition is needed to explain how this cycle occurs. This study therefore proposed causal factors behind the sexual victim-perpetrator cycle from a theoretical standpoint to make up for the lack of past research in this area. This study proposed the following four factors linking sexual victimization and sexual offenses: the victim’s perception of the sexual perpetrator’s positive feelings toward the sexual-offending behavior; the victim’s increasing reinforcement from being sexually victimized; the endangerment of the victim’s masculinity; and the increased accessibility of sexual-offending behavior after being sexually victimized. In addition, past research that looked at family factors and a history of sexual victim experiences was examined. Participants included 472 male inmates from Taipei and Kaohsiung prison and 395 male juveniles from Taoyuan and Changhua juvenile reform schools in Taiwan for a total 867 male participants. An anonymous self-report questionnaire was used to collect data. The results of this study showed that the increased tendency towards sexual-offending behavior after being sexually victimized acted as a mediator of sexual victimization and sexual offenses in the juvenile offenders sample. No single factor had a significant effect on the sexual victim-perpetrator cycle in the adult offenders sample. The increased accessibility of sexual-offending behavior after being sexually victimized had a significant effect, and the endangerment of the victim’s masculinity had a marginally significant effect on the sexual victimization and sexual offense link in the sample of juvenile and adult offenders. Finally, the implications, applications, and limitations of this study, and directions for future research were addressed.