Childhood overweight and obesity have become a primary social and public health concern. Over the past 30 years, rates of childhood overweight and obesity in the United States have increased dramatically from 6% to 35%. A potential risk factor of interest is maternal depression. To date, there are mixed findings available on the association between maternal depression and childhood obesity development, and there is a dearth of longitudinal research available. To address these gaps in the literature, this study investigated the association between maternal depression at age 1 and/or age 3 years and childhood obesity longitudinally. This study used data from the Fragile Families Child Wellbeing Study (FFCWS) to investigate the research questions. FFCWS is a national dataset that has information on 4898 women, and their children, from predominantly nonmarital, low-income minority groups in the United States. This study used information collected at the birth of the child (wave 1) through age 9 years (wave 5). The analytic sample consisted of 3500 mother-children dyads. Group-based trajectory modeling and multivariable logistic regression were used. The results indicated that there was no association between maternal depression and childhood obesity development in this sample of low-income and mostly minority participants. Maternal prepregnancy BMI, number of biological children in the house, and Latino ethnicity were significant predictors of risky growth trajectories in the full sample. Suggestions for designing childhood obesity prevention interventions based on research are discussed.