Diabetes mellitus (DM) is a multifactorial disease associated with cardiovascular complications. Patients undergoing peritoneal dialysis also experience an increased incidence of cardiovascular disease. To prevent progression of cardiovascular complications in DM patients, glycemic control is important. In this study, we examined the efficacy and safety of the glucagon-like peptide analog liraglutide for treating type 2 diabetes patients undergoing peritoneal dialysis. Sixteen type 2 diabetes patients on peritoneal dialysis were enrolled. Before liraglutide initiation, 11 patients were on insulin therapy, three were on oral antidiabetic agents, and two were on diet therapy. Of the 16 patients, 12 had switched to liraglutide because of severe hypoglycemia and four because of hyperglycemia. Echocardiography was performed at baseline and 12 months after liraglutide initiation. Hemoglobin A1c, glycosylated albumin, and fasting/postprandial glucose levels gradually decreased after liraglutide initiation. After 6 and 12 months of treatment, postprandial glucose levels showed a significant difference from baseline. Moreover, the mean daily glucose level and glycemic fluctuations decreased. Systolic blood pressure upon waking also decreased. In addition, after 12 months, left ventricular mass index (LVMI) decreased and left ventricular ejection fraction increased. Changes in LVMI positively correlated with morning systolic blood pressure and fasting glucose levels. One patient restarted insulin because of anorexia but severe hypoglycemia was not observed. These findings suggest that liraglutide therapy in type 2 diabetes patients undergoing peritoneal dialysis is safe and effective for decreasing glucose levels, glycemic fluctuations, and blood pressure, apart from improving left ventricular function.