The Tragedy of Macbeth, one of Shakespeare's four great tragedies, has been subject to various interpretations after its publication. In recent years, feminist criticism, being a comparatively new branch of studies, has been applied to the studies of Shakespeare's plays and new findings keep coming out. Following this trend, this paper chooses to read Macbeth from a feminist's point of view. The centrality of research will be accorded first to Lady Macbeth rather than her husband, and second to the witches. It argues that instead of being an embodiment of evil, Lady Macbeth bravely challenges the established order of a patriarchal society from the following four aspects: her nature, her masculine speeches, her ambition for power and her relationship with her husband. The paper also attaches great importance to the three witches, who are usually ignored in other critics' discussions of Macbeth. It regards the three witches as the ideal candidates for deviant femininity who set traditional notions of men and women at great challenge. Through such radical re-reading of Macbeth, the paper tries to establish a reevaluation of women in Macbeth.