Despite a relationship between gender and support for populist causes in cross-national research, including in the 2016 US Presidential election, the role of gender has been missing in analysis of support for Brexit, most likely because women and men showed no average aggregate-level differences in voting Leave or Remain. This misses an important explanation for Britain’s vote to leave the European Union. We demonstrate how gender-based resentment motivated Leave votes in the EU referendum through perceptions of discrimination against men, among men. Using novel survey measures, we demonstrate (i) the distinct nature of perceptions of discrimination towards men in comparison with discrimination towards women; (ii) the sociological sources of perceptions that men are discriminated against; and (iii) the role of these perceptions in Brexit support. Findings reveal that the Brexit referendum provided an opportunity to express broader social grievances than have, to date, been identified as relevant. The paper therefore offers a novel contribution to understanding the cultural backlash behind Britain’s vote to leave the EU, and by so doing, insight into the potential for gender-based backlash effects in elections where gender isn’t significantly primed, unlike the 2016 US presidential election where gender was a major political focus.