‘Gender (jenda)’ is a troublesome loanword in Japan. While this term has been prevalent in feminist and scholarly circles, it has evoked confusion in the government and stimulated a backlash from the ultra-conservatives against gender equality. Japanese reactionaries have attacked the concept of gender because of their anxiety about cultural destruction – I thus call them the ‘old guard’. Focusing on a dispute over the term ‘gender’ between feminists and the old guard, this paper examines the changes in the term's usage and meanings in the Japanese political context. I first shed light on Japan's reaction to the newly arrived term ‘gender’, outlining different attitudes towards gender between the feminist/scholarly circles and the government. Secondly, I discuss the old guard's condemnation of the concept of gender, in which they distort its significance in order to diminish its positive impact on society. I then scrutinize the old guard's reasons behind their attack on the concept of gender. My findings reveal that the old guard, whose political cause is to protect traditional Japanese culture, asserts that gender equality damages this culture. Moreover, I refute their emphasis on Japan's uniqueness, demonstrating that Japanese women's traditional virtues under the patriarchal family system are not peculiar to Japan. To gauge how the concept of gender has been interpreted politically, I highlight legislative debates about the term ‘gender’. In doing so, I elucidate the extent to which the concept of gender has infiltrated Japanese society through the dispute.