This study examined self-care behaviors and their relationship to glycemic control in low-income Mexican adults with type 2 diabetes in Southeastern Tamaulipas, México. A total of 135 patients were enrolled from 17 community health centers. The most frequent self-care behavior was medication management (80%), and the least frequent self-care behavior was self blood glucose monitoring (7%). All the patients demonstrated poor glycemic control, with glycated hemoglobin > 7%. Self-care behaviors were associated with fasting blood glucose (rs = .223, p = .005). Medication management was influenced by cognitive performance, F(1, 130) = 4.49, p = .036, and depression, F(1, 130) = 8.22, p = .005. Dietary behaviors were influenced by previous diabetes education, F(1, 130) = 6.73, p = .011. These findings indicate that education and cognitive behavioral interventions in Spanish for Mexican adults with type 2 diabetes are urgently needed.