Patriarchal society gives legal rights and economic power to men only so that women are subject to men and imprisoned in private sphere. When women who are given only the role of a wife and mother begin to demand freedom and legal rights, the basis of feminism appears. This study applies liberal feminist approach to George Bernard Shawâs "Mrs Warrenâs Profession" (1893) to analyse the gender roles in terms of patriarchal ideology of separate spheres. Not receiving proper education in patriarchal society, Mrs Kitty Warren becomes a prostitute and then a brothel mistress. As a fallen woman, she exploits her fellow creatures to gain economic power in public sphere. She is conventional at heart like women in private sphere because she wants her daughter Vivie not to work in public sphere but to marry the rich, middle-aged Crofts who is her business-partner of brothels. Being grown up in boarding schools, Vivie Warren, representing the âNew Womanâ type, shakes hands with men, smokes cigarettes, has knowledge of mathematics, graduates from Cambridge, and has the physical strength and intelligence to work in public sphere. Therefore, she refuses her motherâs money, and marriage proposals in patriarchal society in which women are allowed only the role of being a wife and a mother in private sphere. Thus, women and men have no innate difference for mental capacity, but women face prejudices imposed by patriarchal society because it does not allow women to take the same education as men.