ABSTRACT Background: Child marriage is the result of the interplay of economic and social forces. In communities where the practice is prevalent, marrying a girl as a child is part of a cluster of social norms and attitudes that reflect the low value accorded to the human rights of girls. Child marriage has many effects on girls’ health. This study aimed to assess factors associated with early marriage among young women in Blora, Central Java, Indonesia. Subjects and Method: A cross sectional study was carried out in Blora, Central Java, from September to October 2019. A sample of 200 married female was selected randomly. The dependent variable was early marriage. The independent variables were intention, attitude, parental income, peer support, teacher support, culture, female value, subjective norm, and perceived behavior control. Results: The risk of early marriage increased with supportive culture toward early marriage (OR= 5.34; 95% CI= 1.12 to 25.34; p= 0.035), negative female value (OR= 5.27; 95% CI= 1.04 to 26.72; p= 0.045), supportive attitude toward early marriage (OR= 10.2; 95% CI= 1.99 to 52.8; p= 0.005), and weak perceived behavior control (OR= 33.8; 95% CI= 4.18 to 273.67; p= 0.001). The risk of early marriage decreased with peer support toward delayed marriage (OR= 0.09; 95% CI= 0.01 to 0.50; p= 0.006), high parental income (OR= 0.16; 95% CI= 0.03 to 0.87; p= 0.034), parental support toward delayed marriage (OR= 0.07; 95% CI= 0.01 to 0.38; p= 0.002), positive female value (OR= 0.09; 95% CI= 0.01 to 0.45; p= 0.003), weak intention toward early marriage (OR= 0.19; 95% CI= 0.04 to 0.91; p= 0.039), and weak subjective norm (OR= 0.10; 95% CI= 0.01 to 0.59; p= 0.011). Conclusion: The risk of early marriage increases with supportive culture toward early marriage, negative female value, supportive attitude toward early marriage, and weak perceived behavior control. The risk of early marriage decreases with peer support toward delayed marriage, high parental income, parental support toward delayed marriage, positive female value, weak intention toward early marriage, and weak subjective norm. Keywords: early marriage, adolescents, theory of planned behavior Correspondence: Wella Anggraini. Masters Program in Public Health, Universitas Sebelas Maret. Jl. Ir. Sutami 36A, Surakarta 57126, Central Java, Indonesia. Email: [email protected]. Mobile: 081215216795. DOI: https://doi.org/10.26911/the7thicph.03.94