Pneumocephalus is the presence of air in the cranial vault. The common etiologies of pneumocephalus are brain trauma and cranial surgery. We report a case of a 26-year-old man with brain trauma who developed diffuse pneumocephalus after sneezing. CT scan was performed on arrival, and the image showed subarachnoid hemorrhage without pneumocephalus. On the seventh day after a big sneeze brain CT scan was re-performed, which showed pneumocephalus. After another ten days of treatment, the patient was discharged without any symptoms.