Large cranial defects resulting from decompressive craniectomy performed for refractory intracranial hypertension after head trauma is one of the indications for cranioplasty, and this procedure is commonly performed 3 months after craniectomy. However, the large cranial defect would lead to the kinds of complications early during the phase of these patients' recovery, which would go against rehabilitation. This study retrospectively reviewed 23 patients undergoing early cranioplasty (5-8 weeks after craniectomy) in the last 4 years with a detailed choice of patients, outcome of complications after head trauma and large craniectomy, as well as assessment of prognosis. The early outcome (1 month later) revealed most of the patients who had conscious disturbance before the cranioplasty recovered their consciousness and presented an improved neurologic function. The long-dated prognosis (18 months later) revealed that 17 patients were good (independent patients) in this series (74%), whereas four patients survived with a severe disability (17%) and two remained in a vegetative state (9%). No dead patients or intracranial infection after the procedure were found in this study. Most patients' complications were relieved after the cranioplasty with improvements of symptoms or image of computed tomography scan. In conclusion, we consider that with the appropriate choice of patients and materials, early cranioplasty for large cranial defects after decompressive craniectomy would be safe and helpful for the improvement of patients' neurologic function and prognosis. To our knowledge, this series may be the first detailed report in English about early cranioplasty after decompressive craniectomy. We are going to perform prospective and retrospective contrastive studies to further confirm the effects of this procedure on the patients with large cranial defects after decompressive craniectomy.