Penetrating brain injury caused by a nail gun is an uncommon clinical scenario reported in the literature. A 36-year-old male presented with a nail that had penetrated through the occipital bone. He was alert and neurologically intact except for visual disturbance. Computed tomography (CT) of the brain showed the nail lodged at the occipital lobe and the parietal lobe, with minimal intracerebral hemorrhage. The nail was placed in the occipital lobe close to the superior sagittal sinus. We removed the nail with craniotomy since the entrance of the nail was close to the superior sagittal sinus. There were no newly developed neurological deficits postoperatively. Immediate postoperative CT showed no newly developed lesions. The patient recovered well without any significant complications. Two weeks postoperatively, magnetic resonance imaging showed no remarkable lesions. The visual disturbance was followed up at the outpatient department. To summarize, we report a rare case of penetrating head injury by a nail gun and discuss relevant aspects of the clinical management.