Objective To investigate the effect of continuous lumbar drainage combined with decompressive craniectomy on the complications and prognosis of patients with severe craniocerebral injury, and to provide a reference for optimization of surgical treatment in such patients.Methods A total of 184 patients with severe craniocerebral injury who were admitted to our hospital from February 2013 to April 2016 were enrolled and randomly divided into experimental group and control group using a random number table, with 92 patients in each group. The patients in the control group were given decompressive craniectomy, and those in the experimental group were given continuous lumbar drainage in addition to the treatment in the control group. Intracranial pressure (ICP) was measure at 3, 5, and 7 days after surgery, and the Glasgow Prognosis Scale (GPS) score was used to evaluate prognosis at 6 months after surgery. The incidence of postoperative complications such as cerebral edema and cerebral infarction was recorded in detail and compared between the two groups.Results At 3, 5, and 7 days after surgery, the experimental group had significantly lower ICP and a significantly higher GCS score than the control group (P<0.05). Compared with the control group, the experimental group had significant reductions in the incidence rate of cerebral edema after surgery and the degree of cerebral edema (P<0.05). The experimental group had significant reductions in the incidence rate of cerebral infarction after surgery and infarct volume compared with the control group (P<0.05). At 6 months after surgery, the experimental group had a good prognosis rate of 59.78% (55/92), a poor prognosis rate of 33.70% (31/92), and a death rate of 6.52% (6/92), and the control group had a good prognosis rate of 39.13% (36/92), a poor prognosis rate of 50.00% (46/92), and a death rate of 10.87% (10/92); there was a significant difference in prognosis between the two groups (P<0.05).Conclusions Continuous lumbar drainage combined with decompressive craniectomy has a marked effect in the treatment of patients with severe craniocerebral injury and can effectively reduce ICP, improve prognosis, and reduce the incidence of postoperative complications. Therefore, it has a better effect than decompressive craniectomy alone.