The Japanese Supreme Court has recently adopted two judgments with regard to women’s rights, one of which, in particular, will determine a significant change in Japanese legislation in the months to come. On 16. December 2015, the Supreme Court confirmed, in the case最大判平成27年12月16日平成26(オ)1023, that Article 750 the Civil Code did not infringe the principle of non-discrimination enshrined in Article 14 of the Constitution. The provision requires married couples to choose either the wife’s or the husband’s surname as family name. On the same day, the Court argued, in another landmark judgment, 最大判平成27年12月16日平成25(オ)1079, that the remarriage moratorium enshrined in Article 733 of the Japanese civil code, which prohibits a woman to remarry unless six months have passed since the day of dissolution or annulment of her previous marriage, was partially contrary to Article 14 of the Constitution. This article is aimed to first analyse Japan’s international legal obligations, and some provisions of the Japanese civil code, regarding women’s rights which are relevant for the decisions at issue (para. 1); secondly, to briefly illustrate the two judgments rendered by the Japanese Supreme Court (para. 2); thirdly to consider them under the lens of international law (para. 3). We will argue that, despite the reasoning of the Supreme Court, the provision of the civil code providing for the same surname for a married couple seems contrary to the well-established principle of non-discrimination at the international level. Although the wife and the husband can choose the surname they prefer, the majority of couples in Japan choose the husband’s surname, because the role of man as breadwinner is still deeply rooted in that society, as well as in many Western ones. This is the reason why some couples prefer not to get married, in order not to make a choice on the surname, and married women use pseudonyms to continue their job with their maiden names.