This Element aims to critically examine the philosophical thought of Im Yunjidang 任允摯堂 (1721–93), a female Korean Neo-Confucian philosopher from the Chosŏn 朝鮮 dynasty (1392–1910), and to present her as a feminist thinker. Unlike most Korean women of her time, Yunjidang had the exceptional opportunity to be introduced to a major philosophical debate among Korean Neo-Confucians, which was focused on two core questions-whether sages and commoners share the same heart-mind, and whether the natures of human beings and animals are identical. In the course of engaging in this debate, she was able to reformulate Neo-Confucian metaphysics and ethics of moral self-cultivation, culminating in her bold ideas of the moral equality between men and women and the possibility of female sagehood. By proposing a 'stage-approach' to feminism that is also sensitive to the cultural context, this Element shows that Yunjidang's philosophical thought could be best captured in terms of Confucian feminism. This Element presents Im Yunjidang as a Confucian feminist who advocated equality between men and women and female sagehood.