Snake bite is a common clinical problem in Southern Africa. In spite of this, acute renal failure from snake-bite poisoning is extremely rare. Moreover, acute renal failure from puff adder (Bitis arietans) has to our knowledge not been described previously. Two cases of acute renal failure occurring after puff adder venom poisoning were seen within a period of 6 weeks and are described here. Both these patients were maintained on haemodialysis and recovery was uneventful. In both cases, a proliferative nephritis was seen on renal biopsy. It is postulated that the snake venom produced the proliferative nephritis on a hypersensitivity basis.