Female workers in Indonesia are vulnerable, because they must work to earn a living while still being responsible for domestic problems. This study analyzes the barriers to the use of modern contraceptives by female workers in Indonesia's urban areas. This cross-sectional survey looked at 21,696 female workers. We used modern contraceptive use as a dependent variable, and age, education, wealth, known modern contraceptives, number of live births, ideal number of children, and insurance ownership as independent variables. In the final test, we employed binary logistic regression. The results showed that women at all age categories were more likely than those aged 15-19 years not to use modern contraceptives, except those aged 35-39 years, who showed no difference. All other marital types were more likely to use modern contraceptives than married individuals. Rich female workers were 1.139 times more likely than poor workers not to use modern contraceptives (adjusted odds ratio [AOR], 1.139; 95% confidence interval [CI], 1.026-1.264). Female workers who did not know about modern contraceptives were 4.549 times more likely than those who did not to use modern contraceptives (AOR, 4.549; 95% CI, 1.037-19.953). Female workers with more than two children were 9.996 times more likely than those with two or fewer children not to use modern contraceptives (AOR, 9.996; 95% CI, 9.1890-10.875). This study identified five factors associated with the non-use of modern contraceptives by female workers in Indonesia's urban areas: young, unmarried, rich, did not know about modern contraceptives, and had more than two children.