It is well recognized that patients with diabetes encounter a host of daily self-care issues, including controlling blood sugar and preventing and managing complications, which impact significantly upon quality of life. Studies have indicated that learned resourcefulness has a potentially positive effect in dealing with psychosocial and health problems. The purpose of this study was to test the relationship between learned resourcefulness and quality of life in type II diabetic patients. The mediating and moderating effects of learned resourcefulness on the relationship between metabolic control and quality of life of diabetic patients was also examined. This cross-sectional and correlational study included a convenience sample of 131 type II diabetic patients recruited from three hospitals in southern Taiwan. Data were collected through questionnaires, which included the Rosenbaum's Self Control Schedule and World Health Organization's Quality of Life (Short Version). Multiple regression techniques were used to analyze outcome predictors. Study findings include identification of a mediating effect of learned resourcefulness between metabolic control and quality of life. While most DM patients were not satisfied with their health, we found that those with greater learned resourcefulness enjoyed a better quality of life. Learned resourcefulness, gender, and HbA1C explained 35.2% of variance in DM patient quality of life. Male diabetic patients enjoyed a better quality of life than females, even though levels of learned resourcefulness between the two groups were not significantly different. Results indicate that poor metabolic control of diabetic patients has a detrimental effect on quality of life, and when diabetic patients use more self-control skills, they may achieve better quality of life. Results suggest that nurses who use cognitive behavior coping strategies (resourcefulness) may help diabetic patients achieve better metabolic control and promote better quality of life.