This paper reports two cases of rhabdomyolysis following Crotalus durissus terríficus snake bite. The diagnosis of rhabdomyolysis was based upon the presence of severe muscle pain and increased blood levels of CPK, GOT and LDH. In case 2 it was confirmed by the detection of myoglobinemia through serum Immunoelectrophoresis carried out against anti-human myoglobin serum and by a muscle biopsy. This patient- also developed acute renal failure following the snake bite. This complication was attributed to the nephrotoxic and he-molytic venom actions and to the arterial hypotension presented by the patient. The possibility that in this case rhabdomyolysis was also involved in the pathogenesis of acute renal failure can not be ruled out. The patient also presented hypocalcemia, hyperuricemia and hyperphosphatemia during the oligoanuric phase of acute renal failure which are laboratory findings associated with rhabdomyolysis.