Purpose: To study effect of percutaneous transluminal balloon angioplasty (PTA) on dysfunctional stenotic arteriovenous fistulae (AVF). Methods: Between June 2008 to January 2010, 22 patients with dysfunctional stenotic hemodialysis native AVF for whom technically successful PTA were done, were enrolled in the study. AVF dysfunction was shown by a decrease in blood pump flow (Qb) below prescribed level (300-350 ml/min), a decrease in access blood flow rate (Qa) below 400 ml/min and a decrease in urea reduction rate (URR) below 65%. AVF stenoses were diagnosed by duplex ultrasound study and significant stenoses (more than 50% of luminal diameter) were treated by PTA. After PTA, measurements of Qb, Qa, and URR were done and were compared to pre- intervention levels. All AVF were kept on access surveillance program and primary patency rates were assessed at 1, 3, 6 and 12 months. Results: PTA was associated with improvement of AVF hemodynamics as shown by returning of Qb to the prescribed levels with a significant increase by mean of 76(± 26) ml/min (P<0.001) and a significant increase of Qa by mean of 407 (± 92) ml/min (P<0.001) compared to pre- intervention levels. Also PTA was associated with improvement of adequacy of dialysis as shown by a significant increase of URR by a mean of 24.6(± 6.1) % (P<0.001) compared to pre- intervention levels. Primary patency rates of AVF were 95.4%, 68.2 %, 45.4% and 22.7% at 1, 3,6 and 12 months, respectively. Also, primary patency rates were significantly superior in less severe stenoses compared to more severe stenoses with 6 months patency rate of 66.7% versus 20%, respectively (P=0.029). Conclusion: PTA is an effective and safe procedure in the treatment of dysfunctional stenotic haemodialysis native AVF. When successful, it improves AVF haemodynamics, adequacy of dialysis and primary patency rates at short and intermediate terms. Our findings also support the importance of hemodialysis access surveillance programs for early detection of AVF stenosis causing access dysfunction and the pre-emptive PTA which improves access survival