Objective To explore the effect of hypertonic saline combined with magnesium sulfate on severe craniocerebral injury.Methods Patients with severe craniocerebral injury admitted to our hospital from September 2017 to February 2019 were selected prospectively.With the informed consent of the patients' families,the patients were divided into control group and experimental group according to the random number table.Patients in the two groups accepted intracranial pressure monitoring;patients in the experimental group additionally accepted magnesium sulfate combined with hypertonic saline for a continuous use of 7 d.Incidences of high intracranial pressure,epilepsy,low intracranial perfusion,cerebral vasospasm,cerebral infarction,and intracranial pressure rebound,total mannitol dosages one week after injury,serum neuron specific enolase (NSE) level,and Glasgow outcome scale (GOS) scores and mortality rate 3 months after injury were analyzed and compared between the two groups.Results A total of 93 patients were enrolled;47 were into the control group and 46 into the experimental group.There were no significant differences in age,gender,Glasgow coma scale (GCS) scores and NSE levels at admission,and percentages of patients accepted craniotomy evacuation of hematoma or bone flap decompression between the two groups (P＞0.05).As compared with those in the control group,the total mannitol dosage one week after injury and serum NSE concentration were significantly lower,and GOS scores 3 months after injury in the experimental group were significantly higher(P＜0.05).Patients in the experimental group had significantly lower incidences of high intracranial pressure,cerebral vasospasm and intracranial pressure rebound as compared with patients in the control group (P＜0.05).Conclusion Hypertonic saline combined with magnesium sulfate can improve the prognoses of severe craniocerebral injury;it has few side effects and is cheap;it might be an effective cerebral protective agent.