Protein-calorie malnutrition is an important determinant of morbidity and mortality in dialysis patients. Our objectives were to evaluate nutritional parameters including leptin levels and Kt/V in peritoneal dialysis (PD) patients. Twenty-eight PD patients (13F, 15M) were included in the study. Serum leptin, albumin, prealbumin, transferrin, insulin like growth factor-1 {IGF-I), growth hormone (GH), cholesterol, triglyceride, IgG, IgA, IgM, C3 and C4 levels along with body mass index (BMI) and body fat content (BFC) were determined. The mean leptin level was 26.2 ng/ml. The patients' BMI was 24.4 kg/m2 and BFC was 27.1%. The serum values were as follows: albumin: 35 g/L, prealbumin: 40.6 mg/dl, transferrin: 2.5 g/L, IGF-]: 169.3 mg/L, GH: 7.9 mg/L, cholesterol: 5.4 mmol/L, triglyceride: 2.4 mmol/L, IgG: 12.9 g/L, IgA: 1.8 g/L, IgM: 1.1 g/L, C3: 1.5 g/L and C4: 0.3 g/L. The Kt/V was measured in 20 of the patients and its mean value was 2.1. No significant correlation was established between leptin levels and Kt/V nor any other parameters other than BMI, albumin, C3 and C4. Our results demonstrated that serum leptin level is elevated and it could only partially serve as a biochemical marker for nutritional status in PD patients.