SummaryPatients who have undergone a surgical procedure without infection show an important increase of the alcaline phosphatase in serum. The same thing was noticed after severe hemorrhage, also after extensive burns and in two cases with ischemic gangrene of the lower limb.In dogs such a hyperphosphatasemia was produced by a rapid and important bleeding; reinjection of the blood into the peritoneal cavity increased the phenomenon.The hyperphosphatasemia is not immediate; it is not linked to the hyperglycemia that follows the traumatic shock, no more to the hyperthermia because it was observed in cases without temperature such as severe bleeding or ischemic gangrene of the limbs.Work is performed to elucidate the origin of the hyperphosphatasemia observed in surgical conditions.