Pneumocephalus is air in the cranium commonly seen in postcraniotomy and in head injury patients. When this air causes an increase in intracranial pressure leading to neurological deterioration, it is called tension pneumocephalus. Similarly, intraventricular air causing compression on vital centers and increasing intracranial pressure is called tension pneumoventricle, and this causes expressive aphasia, which is rarely described in the literature. This study reported a case of a traumatic cerebrospinal fluid (CSF) leak leading to tension pneumoventricle and aphasia. Case: A young male patient sustained severe head injury and had extradural hematoma (EDH) and multiple skull and skull base fractures. EDH was drained, and he recovered and was discharged with a Glasgow coma scale score of 15. He presented to neurosurgical outpatient with CSF leak, aphasia, and loss of bowel and bladder control for a duration of three days. Computed tomography brain scan showed tension pneumoventricles, and he was started on conservative management. His general condition deteriorated, and the next day, his pupils became unequal, and Glasgow coma scale (GCS) dropped to 8/15. He was immediately taken to theater, and the air was aspirated from the ventricles, and an external ventricular drain was inserted. The patient woke up in the immediate postoperative period and started talking normally by day four. Conclusion: Tension pneumoventricles should be considered a cause of aphasia. Immediate intervention and reduction of intracranial pressure are crucial to reverse neurological abnormality and improve patient's outcome.