Continuous ambulatory peritoneal dialysis (CAPD) is commonly used for renal replacement therapy in diabetes mellitus (DM) patients. We investigated the changes of peritoneal transport characteristics, nutritional status, and adequacy and inflammation parameters in diabetic CAPD patients (N = 17) compared to non-diabetic patients (N = 23). Peritoneal equilibrium testing, nutritional, biochemical, and anthropometric parameters and adequacy were prospectively assessed at 1 (baseline), 6 and 12 months after initiating CAPD. The levels of several nutritional parameters were lower and did not change in DM patients over time (P < 0.05) and significantly improved in the non-DM patients over time (P < 0.05). Total weekly creatinine clearance and residual renal function exhibited a rapid decline (P < 0.05) and inflammation parameter levels were higher in DM patients (P < 0.05). Our results showed the difficulty in improvement of nutritional status and inflammatory parameters in diabetic patients during at least the first year of CAPD compared to non-DM patients.