Throughout the twentieth century, Taiwan and South Korea underwent rapid economic development and successfully democratized without reversal to authoritarianism. Despite their similar trajectories, the two countries diverge significantly in political and public support for gender equality. Taiwan is widely seen as the most gender-equal country in Asia, while South Korea remains deeply polarized, with uneven progress in women’s representation. What accounts for this divergence between two democracies? This article advances a political institutions thesis, arguing that differences in democratic institution-building—particularly the actors and modes of democratization—have shaped the contour of gender politics of each country. Contrasting the histories of party-driven democratization in Taiwan and mass-driven democratization in South Korea, this article shows that the process of building democracy has had lasting effects on the institutionalization and sustainability of gender equality.