Intracranial complications of pediatric sinusitis are rare but potentially life threatening. These complications include cavernous sinus thrombosis, orbital infection, meningitis, and subdural empyema. Children with these complications may experience significant morbidity from their infection. In such cases, delay in diagnosis and treatment may lead to severe brain damage or death. Emergency physicians, pediatricians, and otolaryngologists should maintain a high index of suspicion for this complication of disease when treating patients with sinusitis in the emergency department or outpatient clinic. Early and accurate diagnosis of subdural empyema will lead to prompt treatment and a favorable outcome for the patient. We report a case of subdural empyema secondary to frontal sinusitis in an otherwise healthy immunocompetent adolescent boy.