This essay treats of several problems of sex in Japanese traditional music. It contains the following items. (1) The different rolls of man and woman in Japanese primitive time. (2) Some definite kinds of music and musical instruments, played only by men or only by women ; and those reasons. (3) The womanly character in some Japanese music. (4) The special object and meaning of texts concerning sexual love in ancient religious songs. (5) The special methods of expression of "manly" and "womanly" in some Japanese vocal music.