Social cohesion is an important resource for families living in conditions of poverty. Principles of cohesion such as the ability to establish positive relationships and build trust with neighbors are particularly important in preventing or reducing problems related to poverty such as food insecurity. Longitudinal data from a stratified probability sample of 1,495 low-income mothers living in Boston, Chicago, and San Antonio are used to test whether changes in individual perceptions of neighborhood social cohesion are associated with food insecurity. Results reveal that the magnitude of neighborhood social cohesion and changes in magnitude over time are significantly related to the likelihood of experiencing food insecurity. The implications of these findings for policies and interventions aimed at promoting neighborhood social cohesion and reducing food insecurity are noted.