The purpose of this study was to investigate the sexual knowledge and the needs of sex education for college students in order to develop sex education program. The data were collected from 271 students attedning K community college in Chungcheongbuk-do from November, 29 to December 3, 1999, using a self-administered questionnaire. Sexual knowledge in this study include 4 areas such as sexual physiology, contraceptive methods, venereal disease. and reproductive physiology. The results were as follows : 1. The mean score of the knowledge in sex was 15.42 out of 29, which is very low. Of the four areas of the knowledge, the students showed the lowest score in contraceptive methods. Woman students had significantly higher score in reproductive physiology than man students. 2. Seventy nine percent of the students felt the need for sex education being given by their college. Most students wanted to obtain sex education through special lectures $(55.7\%)$ or regular curriculum$(29.2\%)$, Those specialists in sex education were most prefered. with regard to the contents of sex education, sexual psychology was most frequently indicated followed by contraceptive methods, pregnancy, satisfy ways of sexual drive. About forty two percent of the students thought preschool age as the adequate stage for beginning sex education. 3. Sexual knowledge was statistically significant in terms of grade. major. and dwelling state.