Abstract The purpose of this study was to evaluate the efficacy of a home-based nursing program in the diabetic control of elderly people with diabetes mellitus living alone. Patients meeting the sampling criteria were recruited from a medical center and 10 health centers in Taipei for this quasi-experimental study. By matching the effects of age, sex, education, and history of diabetes, subjects were assigned semirandomly to two groups based on the intensity of home-based nursing care visitations. Group I was defined as daily visits to supervise diet, exercise, medication, and self-monitoring blood sugar (n = 15) and Group II as weekly visits to supervise diet, exercise, medication education, and self-monitoring blood sugar (n = 15). Patients who agreed only to receive blood examination were assigned to the control group (n = 14). The results of the study showed that reductions in fasting blood sugar, postmeal blood sugar, and hemoglobin A1c (HbA1c) in Groups I and II were significantly greater than those in the control group. The reduction in the total cholesterol and low-density lipoprotein in Groups I and II was significantly greater than that in the control group. There were no significant differences among the three groups in the improvement of high-density lipoprotein (HDL) and triglycerides (TGs). Group I revealed a significantly greater weight reduction compared to Group II. There was no significant difference between Groups I and II in the improvements of diabetes knowledge, depression level, or quality of life. From the research findings, based on cost-effectiveness, it is recommend that Program II be implemented.