Arteriovenous fistula (AVF) maturation failure is the primary cause of dialysis vascular access dysfunction. To evaluate whether preoperative vascular functional properties predict postoperative AVF measurements, patients enrolled in the Hemodialysis Fistula Maturation Study underwent up to five preoperative vascular function tests (VFTs): flow-mediated dilation (FMD), nitroglycerin-mediated dilation (NMD), carotid-femoral pulse wave velocity, carotid-radial pulse wave velocity, and venous occlusion plethysmography. We used mixed effects multiple regression analyses to relate each preoperative VFT to ultrasound measurements of AVF blood flow rate and venous diameter at 1 day, 2 weeks, and 6 weeks after AVF placement. After controlling for AVF location, preoperative ultrasound measurements, and demographic factors (age, sex, race, and dialysis status), greaterNMDassociatedwith greater 6-weekAVF blood flowrate andAVF diameter (per absolute 10% difference in NMD: change in blood flow rate =14.0%; 95% confidence interval [95% CI], 3.7% to 25.3%; P,0.01; change in diameter =0.45mm; 95%CI, 0.25 to 0.65mm; P,0.001).GreaterFMDalso associated with greater increases in 6-week AVF blood flow rate and AVF diameter (per absolute 10% difference in FMD: change in blood flow rate =11.6%; 95% CI, 0.6% to 23.9%; P=0.04; change in diameter =0.31 mm; 95% CI, 0.05 to 0.57 mm; P=0.02). None of the remaining VFT parameters exhibited consistent statistically significant relationshipswith both postoperative AVF blood flow rate and diameter. In conclusion, preoperativeNMD and FMDpositively associatedwith changes in 6-week AVF blood flow rate and diameter, suggesting that native functional arterial properties affect AVF development.