Using data from the Programme for the International Assessment of Adult Competencies, this study examined gender differences in participation in various forms of nonformal learning -- on-the-job training, distance learning, workshops and private lessons -- and their relationships with earnings in South Korea. The authors found significant gender differences in participation in on-the-job training, distance learning, and workshops favouring male workers, but the reverse gender gap in participation in private lessons favouring female workers. When it came to earnings, the authors found the positive relationships between participation in distance learning and earnings and between workshops and earnings for both males and females, even after controlling for other variables. However, the positive relationship between participation in on-the-job training and earnings was observed only for females. The authors highlight some unique aspects of Korea's organisational culture that may help explain the relationships among gender, on-the-job training and earnings. Broader implications of the findings beyond South Korea are also discussed.