The purpose of this article is to redefine the gender using Allameh Tabataba'i’s theory of Itibariat. The gender has no corresponding equivalent in Islamic philosophy. The study shows that the words masculinity and femininity do not correspond to the feminist sociology terms of gender, and using these words interchangeably in research on gender and Islamic philosophy causes a conceptual fallacy. In the works of Muslim philosophers, there is no concept that covers the various dimensions of the concept of gender, including its natural, cultural and social aspects, and is based on Islamic philosophy. Allameh's Itibariat theory, with its careful look at the necessity of the social dimension and issues of human sciences, has a suitable capacity for theorizing in the fields of Islamic social sciences and humanities, including redefining the concept of gender. Realism, the aspect of stability (essentialism) at the same time as the aspect of change and fluidity, are the foundations implied in the concept of gender based on the theory of Itibariat. Gender, as a social Itibar, is subject to the rules of post-social Itibariat; However, pre-social Itibariat are also influential in the concept of gender.