Defined as an inability to acquire enough food because of insufficient money or other resources, the prevalence of food insecurity is markedly higher among cancer survivors than the general population. The objective of this qualitative study was to understand and characterize the experience of food insecurity from the perspective of cancer survivors' and their informal caregivers using qualitative interviews. Barriers to healthy eating, behaviors and strategies in times of food shortage, and unmet educational needs shaped the experience of food insecurity. These experiences and insights for addressing food insecurity in oncology practice have broad implications for future interventions.