This article explores the taboo surrounding menstruation in Korea, which has its roots in Confucianism and affects many aspects of Korean society, from education to healthcare. The lack of education about periods, euphemisms used to describe them, cultural norms of modesty and propriety, negative media representation, religious beliefs about impurity, and stigma and discrimination against women who experience them all contribute to this taboo. However, advocacy efforts such as "Period Positive" are working to break this taboo and promote education and awareness about menstruation.