Abstract The gender gap in support for trade is one of the most robust empirical findings to emerge from research on public opinion in international political economy. Even controlling for differences in education, skill level, industry affiliation, and other factors, women express consistently more protectionist views than men. Less frequently noted, and thus far unexplained, is that this gender gap varies cross-nationally. We advance an explanation that draws attention to national differences in gender discrimination, predicting that the gender gap will be larger in countries with greater gender discrimination. Using two decades of public opinion data across twenty-two OECD countries and measures of de facto and de jure gender equity, we conduct three separate empirical analyses of the relationship between levels of equity, women’s trade attitudes, and the gender gap. The results support the contention that unequal gender treatment is an important driver of the gender gap in trade attitudes.