High levels of neighborhood deprivation and lack of access to supermarkets have been associated with increased risk of obesity in women. This multilevel study used a statewide dataset (n = 21,166) of low-income women in the Special Supplemental Nutrition Program for Women, Infants, and Children to determine whether the association between neighborhood deprivation and BMI is mediated by the availability of retail food stores, and whether this relationship varied across the urban rural continuum. Residence in a high deprivation neighborhood was associated with a 0.94 unit increase in BMI among women in metropolitan areas. The relationship between tract deprivation and BMI was not linear among women in micropolitan areas, and no association was observed in rural areas. The presence of supermarkets or other retail food stores did not mediate the association between deprivation and BMI among women residing in any of the study areas. These results suggest that level of urbanity influences the effect of neighborhood condition on BMI among low-income women, and that the availability of supermarkets and other food stores does not directly influence BMI among low-income populations.