Objective This study explored fast food intake as a potential mediator of the relationships among employment status; stress; depression; and fruit, vegetable, and fat intakes by race (African American vs. Non-Hispanic White) and body mass index (BMI category: overweight vs. obesity). Methods Low-income overweight and obese pregnant women (N = 332) were recruited from the Special Supplemental Nutrition Program for Women, Infants and Children in Michigan. Path analysis was performed to explore mediation effects by race and BMI category. Results Fast food intake mediated the relationship between employment status and fat intake (p = 0.02) in Non-Hispanic White women, but no mediation effect was detected in African American women. For overweight women, fast food intake mediated the relationship between employment status and fat intake (p = 0.04) and the relationship between depression and vegetable intake (p = 0.01). Also, fast food intake partially mediated the relationship between depression and fat intake (p = 0.003). For obese women, fast food intake mediated the relationship between employment status and fat intake (p = 0.04). Conclusion Fast food is an important topic for nutrition education for overweight and obese pregnant women. Future interventions may be more successful if they address issues associated with employment status (e.g., lack of time to plan and cook healthy meals) and depressive mood (e.g., inability to plan meals or shop for groceries when coping with negative emotions).