The availability of an adequate household food supply is critical for the older population. There is little work that has examined food security and the influence of nativity on food security among older Mexican Americans living along the Texas-Mexico border. Using data from 140 older women (age ≥ 50 y) who participated in the 2009 Colonia Household and Community Food Resource Assessment (C-HCFRA), we examined demographic characteristics, health characteristics, food access and mobility, federal and community food and nutrition assistance programs, quality of food environment, food security, eating behaviors, and alternative food sources. 77% of participants experienced food insecurity, with 68% experiencing very low food security. Very low food security was associated with being born in Mexico, adjusting for household income and food assistance program participation. This article provides compelling evidence for enhanced research efforts that will better understand coping strategies and the use of food and nutrition assistance programs for reducing hardship associated with very low food security among older U.S.- and Mexico-born Mexican American women.