Background: The use of temporary or permanent venous catheters in patients with renal failure has been increased recently. Therefore, familiarity with their clinical applications and complications is essential. This study aimed to evaluate the complications and effectiveness of temporary and permanent venous catheters.Methods: This was a prospective study conducted in Alzahra Hospital during 2006-2008. Patients with renal failure candidate for placement of either permanent or temporary central venous catheter were evaluated for early and delayed complications immediately after placement, as well as one and four weeks afterward. Data was analyzed using chi-square test in SPSS16. P values less than 0.05 were considered as significant.Findings: Overall, 114 patients with temporary and 129 patients with permanent catheters participated in this study. The majority of complications among the temporary catheter group were infection (15.3%) and bleeding (5.4%). In the permanent catheter group, the most frequent complications were infection (13.6%) and venous thrombosis (13.6%). Venous thrombosis rate in the temporary catheter group was significantly lower than the permanent catheter group (P < 0.01). The frequency of catheter malfunctions in the temporary and permanent catheter groups were 23.4 % and 6.4%, respectively. Therefore, there was a significant difference between the two groups (P < 0.001).Conclusion: Since permanent catheters have prolonged and better function than temporary catheters, they are the first and best method of central venous catheterizing for hemodialysis. However, due to the lower venous thrombosis rates of temporary catheters, they are preferred in patients with proper indications for arteriovenous fistula (AVF) until the maturation of AVF.