Three studies explored women's bifurcation of feminine identity as a response to threatening stereotypes in the domain of mathematics. Study 1 demonstrated that women in a math class who previously had completed a large number of math courses disavowed ''feminine characteristics'' strongly associated with stereotypes about women's potential for math success (e.g., flirtatiousness, planning to have children) but not characteristics perceived to be weakly associated with these stereotypes (e.g., empathy, nurturance), more than women who had completed fewer math courses. Studies 2 and 3 directly manipulated stereotype threat by presenting a scientific article reporting stereotype-consistent sex differences in math aptitude. As predicted, women strongly identified with mathematics responded to this threatening article by disavowing feminine characteristics strongly associated, but not those weakly associated, with the relevant negative stereotypes, while women not strongly identified with mathematics showed no such differentiation in response. Theoretical and practical implications of these results are discussed.