This study examined the prevalence of and risk factors for sexual abuse of boys in South Korea by asking a national sample of 1,043 adult males whether they had experienced sexual abuse during childhood. The results indicate that 13.5% experienced at least one of the nine types of child sexual abuse assessed. In addition, the majority of the sexually abused did not seek professional help at the time. The risk factors for sexual abuse include children's involvement in delinquent behaviors, lower family economic status, and residence in small cities. Findings from this study indicate that sexual abuse of boys is a serious problem in Korea, one that calls for enhanced public understanding of the issue as well as effective services and policies designed to prevent or intervene in sexual abuse.