Captopril and Allopurinol have protective effect against renal warm ischemia with different mechanisms. We evaluated this protective effect against 1 hour warm ischemia induced in dog's kidneys. In this experimental study we performed an operation in 15 healthy dogs. During thses procedures both kidneys was clamped for 1 hour then left kidney were removed for pathologic evaluation and right kidneys remained insitue for functional assessment. Five random dogs received 1 mg/kg/day Captopril orally before and after surgery (Captopril group) another five dogs received 10 mg/kg/day Allopurinol orally before and after surgery (Allopurinol group) and reminder five dogs received no drugs as a control group. Serum urea and creatinine were measured preoperatively and on postoperative days 1,3,5,10 and 16 in all groups. Serum levels of urea and creatinine elevated in all groups but in captopril group maximum levels of urea and creatinine were significantly lower than control (P<0.05) In Allopurinol group the maximum rise of creatinine were significantly lower in comparison to control group (P<0.05) but the maximum levels of urea in this group have no significant difference when compared with control values . (P<0.05) There was no significant difference in pathologic change in three groups. In conclusion, one hour warm ischemia result to ATN so it is not safe for dog's kidneys. Althogh Captopril and Allopurinol can not prevent ATN after one hour warm ischemia but can reduce its severity and can improve renal function after warm ischemia.