In Nepal, as in other Asian countries, the issue of sexuality still remains a taboo. Despite this fact, an increasing number of sexual activities is being reported by Nepalese students. The main objectives of the study are to examine students' attitudes toward premarital sexual relationship and to assess students' prevalence of premarital sexual intercourse. A large variation in attitude regarding female and male virginity at marriage was observed by sex. Boys have liberal attitude towards female and male virginity at marriage. Acceptance of premarital sex was less prevalent among girls than boys. The study found that individual, family and peer characteristics had the main effects on premarital sex. Despite strong social and cultural taboos, college students in Nepal are not only involved in premarital sex but also in risky sexual behavior. Young people are exposed to health hazards due to their sexual behavior; hence sex education should be provided. School or college based sexuality education could benefit even out-of-school youths, because their partners often are students.