Vascular calcification and increased oxidative stress are commonly seen in patients with end-stage renal disease (ESRD). Nitrotyrosine is one of the end products of nitric oxide metabolism and is accepted as an indicator of oxidative stress. Nitrotyrosine levels have been found to be high in ESRD patients. The aim of our study is to investigate the relation between coronary artery calcification and oxidative stress in peritoneal dialysis (PD) and hemodialysis (HD) patients. 46 PD and 34 HD patients are included in the study. Coronary artery calcification scoring (CACS) is made by multi slice computed tomography. Patients are divided into 4 groups according to their CACS values as Group 1 (CACS: 0), Group 2 (CACS:1-99), Group 3 (CACS:100-399) and Group 4 (CACS: ≥400). Serum nitrotyrosine levels were measured. Nitrotyrosine levels were significantly increased in HD patients compared to PD patients. Nitrotyrosine levels were found to be elevated in accordance with increased CACS in PD patients. However, we could not find this relationship in HD patients. There might be an important relationship between CACS and oxidative stress in PD patients.