PURPOSE: We designed this study to find out the risk factors affecting the patency rate after creation of arteriovenous fistula (AVF) for maintenance hemodialysis. METHODS: From March 1997 to April 1999, a total of 206 AVF creation operations [126 of radiocephalic fistula (RCF), 59 of brachiocephalic fistula (BCF), and 21 of grafted fistula] in 165 patients were undertaken by single surgeon under the same surgical technique and principles. In 128 cases (62.1%), operation was performed for the first time and in 42 cases (20.4%), the trial was second time. However in remaining 36 cases (17.5%), the operation was three or more than three times. RESULTS: After a mean follow-up of 9 months, 27 patient death and 53 fistula failure were identified. The overall patency rate at 1- and 2-year were 72.6% and 61.1%. The success patency rate, excluding the early failure cases, at 1-and 2-year were 78.4% and 65.9%. In multivariate analysis, the presence of 2 or more than 2 times failed AVF episodes was the significant risk factor forecasting the poor fistula patency (p<0.05, odd ratio=2.72). Although the odd ratio in patients with grafted fistula or in diabetic patients was 1.39 or 1.48 in multivariate analysis, these factors did not reach the statistical significance in multivariate analysis (P>0.05). In univariate analysis, the 1- and 2 year patency rate of more than third AVF trial group were 53.2% and 25.3%, which showed significant poor patency rate comparing with the ones of first or second AVF trial group (76.73% in 1- and 67.9% in 2-year) (p=0.0197). CONCLUSION: In conclusion, repeated trial of AVF creation (= or >3) in itself was the most powerful significant risk factor affecting the patency rate after AVF creation. The successful first or second trial is very important to expect a long-term patency. Well designed surgery under delicate surgical technique in early referred patient should promise the long-term patency even in patients with diabetes or patients requiring grafted fistula.