In the United States, people perceive men’s masculinity to be more precarious, or easier to lose, than women’s femininity. In the present manuscript, we investigated (1) whether men’s heterosexuality is likewise perceived to be more precarious than women’s, and if so, (2) whether this effect is exaggerated when the targets in question are Black rather than White. To investigate these questions, we conducted a large-scale (N = 3,010), nationally representative experiment in which participants read about a target person who either did or did not engage in a single same-sex sexual behavior. Results revealed that participants questioned the heterosexuality of men more than the heterosexuality of women when they engaged (vs. did not engage) in a same-sex sexual behavior. Surprisingly, these effects were not moderated by whether targets were Black vs. White. In other words, men’s heterosexuality was indeed perceived to be more precarious than women’s, irrespective of targets’ race.