OBJECTIVES: To examine physical and mental health domains of health-related quality of life (HRQL) in a binational adult population with type 2 diabetes at the Texas-Mexico border, and to explore individual and social correlates to physical and mental health status. METHODS: Adults 18 years and older with type 2 diabetes residing in the South Texas Lower Rio Grande Valley and in Reynosa, Tamaulipas, Mexico, were recruited using a convenience sampling technique and interviewed face-to-face with a structured survey. HRQL was measured using physical and mental health summary components of the Medical Outcomes Study Short Form. HRQL correlates included demographic characteristics, health factors, access to healthcare, and family support. Samples characteristics were compared using the Students t-test or Mann-Whitney U test. Associations between dependent and independent variables were examined using unadjusted and adjusted (multiple variable) logistic regression models. RESULTS: There were no significant differences between Valley and Reynosa respondents in physical or mental health status scores. Valley participants with lower socioeconomic status and those perceiving their supportive relatives level of diabetes-related knowledge as "low" were more likely to report worse physical health than those lacking those characteristics. In the Reynosa group, lower physical health status was associated with duration of diabetes and insulin use. Both sample populations with clinical depressive symptoms were more likely to have worse physical and mental health than those without such symptoms. CONCLUSIONS: HRQL is an important outcome in monitoring health status. Understanding the levels and influences of HRQL in U.S.-Mexico border residents with diabetes may help improve diabetes management programs.