<p>Whether men who have sex with men see themselves as sexy is influenced by their gender expression – that is, by their performance of masculinity and femininity. Generally, while masculine men attract others’ sexual interest, feminine men are relegated to the sexual margins. Hegemonic masculinity underpins the disproportionate value gay communities place in masculinity over femininity. Yet norms of gender expression and sexual desirability also vary between gay subcultures. Here, we tested the relationships between sexually desirability, masculinity, and femininity, and whether these relationships were moderated by participants’ membership in a gay subculture. Using dynamic structural equation modelling, we analyzed experience sampling data from 234 Grindr users (<i>T</i> = 12,162) collected in May 2022. We found that masculinity, but not femininity, was associated with how sexually desirable Grindr users felt, but only limited evidence that these relationships differed between subcultures. When participants felt more masculine (<i>β</i> = .09) they felt more sexually desirable, and vice versa (<i>β</i> = .16). Our data suggest anti-effeminacy may act via masculinity and not femininity to affect whether men who have sex with men feel sexually desirable. The pressure to be sexy may lead men who have sex with men to invest in masculinity. In doing so, they may risk perpetuating anti-effeminacy, among other forms of discrimination.</p>