Even though the rate of infection of HIV is very low compared to other countries, data show a steady rise in HIV infection rates among young people in South Korea. A peer education program was provided to prevent the incidence of AIDS in young people. The program used peer leaders to provide AIDS related information and counseling for middle school students. Peer leaders received special training in AIDS related education and counseling to assist their friends. Peer leaders worked with their mends in one-to-one or small group settings. A pretest-posttest control design (six months after intervention) was used to evaluate the effects of the peer education program for prevention of AIDS. A post-intervention survey found that do you mean six months after the program or after six months of programs of peer program activities, the experimental groups(groups with peer educators) showed better knowledge, more positive attitudes, and less sexual activity when compared to control groups of non-participants(groups without peer educators). Peer leaders showed significant gains in knowledge about HIV transmission, more positive attitudes and self-efficacy not to engage in high-risk behaviors. Peer education was an effective tool for increasing knowledge, improving attitudes and self-efficacy, and encouraging appropriate behavior change.