Previous literature documents a strong relationship between food insecurity and mental health, and also examines the impact of safety net programs on food insecurity. However, little is known about the intersection between mental health, safety net participation, and food insecurity. In this research, we use a multi-program safety net calculator (including cash, food, and health insurance programs) and data from the National Health Interview Survey and the Current Population Survey to examine the effects of safety net generosity on food insecurity and mental health for single mother families. We examine four research questions. First, does state safety net generosity affect self-reported participation in safety net programs? Second, does mental health affect participation in safety net programs, conditional on generosity? Third, does more generous cash and food assistance affect mental health? And finally, how effective is the safety net in reducing food insecurity in the presence of mental health issues? We find that state-level safety net generosity does predict self-reported participation, and that conditional on generosity, those with mental health issues are significantly more likely to participate in safety net programs. More generous cash and food assistance is protective of maternal mental health, but results are somewhat sensitive to the measure of mental health examined. Finally, we find no effect of the safety net on 30-day food insecurity. These results have important implications for the effectiveness of safety net programs for some of the most vulnerable members of society: low-income mothers suffering from mental health challenges and their children.