Previous research suggests that people from some religious backgrounds hold more negative attitudes towards gay men than others do. The current research focuses on psychological variables as an alternative explanation to religious affiliation, testing whether masculinity beliefs regarding gay men and their perceived threat to one's masculinity can explain such between-group differences in negative attitudes. With a sample of 155 male heterosexual university students (Muslims and Christians in Germany), we found that Muslims held more negative attitudes towards gay men than Christians did. Yet, this relation was partially mediated by beliefs about the masculinity of gay men and the experience of masculinity threat imposed by gay men, substantially reducing the effect of religious affiliation on antigay attitudes. In sum, similar psychological processes explained antigay attitudes of both Muslims and Christians. Copyright © 2013 John Wiley & Sons, Ltd.