The current study explored the relation between sexual orientation, masculinity ideology, and sexism among 380 adult heterosexual and bisexual women. Participants completed measures of sexual orientation, masculinity ideology, hostile sexism, and benevolent sexism. Mean-level analyses concluded that heterosexual women scored significantly higher on hostile and benevolent sexism than their bisexual counterparts. Findings from the regression analyses revealed that masculinity ideology predicted both hostile and benevolent sexism. Sexual orientation only moderated the association between masculinity ideology and hostile sexism, such that the effect was stronger for heterosexual women. Sexual orientation did not moderate the association between women's masculinity ideology and benevolent sexism, suggesting that women's relationship with benevolent sexism may be more complex. The current findings suggest that heterosexual women's conceptions of gender-role attitudes toward men and women may be more salient and potentially harmful compared to bisexual women, and heterosexual intimacy may be an important factor to consider.