During kidney transplantation in spite using ideal surgical and anaesthesiological technique,in some cases microvascular spasm of cortex prevents immediate and adequate diuresis. In this study we assessed whether relief spasm by using vasodilator agents can increase diuresis and hence better function of graft. From April 2000 - October 2005, 415 renal transplantations performed in our center by one surgical team. These recipients were included prospectively in this study after gaining consent and observing medical ethics. The patients divided in 3groups. Group A (Papaverin + Furozemide) Group B (Lidocaine+Furozemide) Group C (only Furozemide). Papaverine or lidocaine injected into artery of graft before vascular anastomosis. Conventionally for all recipients we injected 100mg Furozemide before anastomosis. Immediate diuresis and urine out put at different time with serum creatinine were measured and compared between 3 groups. Immediate diuresis occurred in 99% group A and 96% group B and 93% group C (P= 0.01). Urinary out put at 2, 8, 24 hrs after operation in groupA and group B was significantly higher than group C (P <0.001). Serum creatinine levels 1,4 weeks after transplantation were also lower in groups A&B than group C. These results is not different significantly between group A&B. Our results suggest that injection of papaverine and lidocaine into artery of graft before vascular anastomosis have antispasmodic effect on microvascular of cortex and can improved perfusion and induce more urinary out put and better renal function.