With complicated and diverse society these days, the information about sexuality is flooded and many behaviors related to the expression of sexual desire are on the rise as a social problem. Since sexuality has been regarded shameful in Korea, making it public has been tabooed and this traditional idea has swayed society. In other words, the traditional idea was formed through social convention that considers sex as the subject of inhibition and control, leading to exclusive culture about sex traditionally. Even such a social and cultural characteristic has affected the whole curricula in school. Because of this social and cultural characteristic, the emphasis on the need of sex education in school has difficulty in practice. Human being\'s sexuality includes a variety of aspects: reproduction which leaves offspring; and pleasure, sociality, and mentality which satisfy sexual desire. The sex education conducted in school is the course of instructing the matter of reproduction and sexual behavior and delivering the moral value of sex. There are many different views about how the course is achieved according to researchers. This study examines that how we see sex education as a part of human education in consideration of the actual conditions of the Western countries and discusses the sex education conducted in school. Key words : Sexuality, Sex Education, School.