The daily rehydration volume of patients with craniocerebral injury should be controlled at 1500~2000 milliliters, of which saline is not more than 500 milliliters. After craniocerebral injury, the speed of rehydration should not be too fast, and the amount of rehydration should not be too much to prevent aggravating the phenomenon of cerebral edema. Craniocerebral injury is mostly caused by trauma, and its clinical symptoms vary according to the trauma site, often appearing consciousness disorder, neurological dysfunction, increased intracranial pressure and other manifestations. After craniocerebral injury, all of them have to go through the cerebral edema period, and a large amount of infusion has the danger of aggravating cerebral edema, so the amount of postoperative infusion should be controlled at 1500~2000 ml. In addition, patients in the cerebral edema stage need to use dehydrating agents, so in the infusion at the same time should pay attention to maintain the water electrolyte balance, such as additional loss should be appropriate to replenish. Craniocerebral injury patients should be under the guidance of the doctor according to the 24-hour in and out of fluid replenishment, to avoid cerebral edema symptoms continue to worsen.