Comparisons of mortality rates in patients with end-stage renal disease (ESRD) on peritoneal dialysis and hemodialysis have been inconsistent. The aim of the study was to reveal the possible effect of comorbidity on differential survival in these two groups. 210 hemodialysis and 95 peritoneal dialysis patients were enrolled in this study who underwent dialysis treatment in the nephrology department of national centre of urology in Tbilisi between January 2004 and December 2006. Peritoneal dialysis was used by 9% of patents as baseline, 21% at twelve months and 26.5% at twenty four months. The mean follow-up was 24 months, with a maximum follow-up time of 36 months. The total co-morbidity was higher in hemodialysis compared to peritoneal dialysis patients at baseline, 12 months and 24 months. The mortality was similar in the groups defined by the mode of dialysis. Based on the results of the study, it is to conclude that, hemodialysis and peritoneal dialysis, as two different modalities of renal replacement therapy in the patients with ESRD, are associated with similar overall survival rates in Georgia. The apparent survival advantage of peritoneal dialysis may be due to lower co-morbidity and a lower burden of acute onset ESRD at the inception of dialysis.