Among the millions of entrepreneurs in developing economies, few are able to earn a decent livelihood. To help these entrepreneurs succeed, governmental and nongovernmental organizations invest billions of dollars every year providing training programs. Many of these programs involve providing entrepreneurs with mentors. Unfortunately, the effects of these programs are often muted, or even null, for women-owned firms. Against this backdrop, we tested whether gender-matching, where female entrepreneurs are randomly paired with a female mentor, could help address the gender gap. Findings from a randomized controlled field experiment with 930 Ugandan entrepreneurs show that although mentor gender has little impact on male entrepreneurs, it has a powerful impact on female entrepreneurs. Firm sales and profits of female entrepreneurs guided by a female mentor increased by, on average, 34% and 29% compared to the control group, and these estimates are even larger for female entrepreneurs with high aspirations. In contrast, female entrepreneurs guided by a male mentor did not significantly improve performance compared to the control group. We provide suggestive mechanism evidence that female mentor-mentee arrangements are characterized by more relational exchanges.