BACKGROUND: Cavernous angiomas (cavernomas) are vascular malformations of the brain characterized by abnormal capillaries. Ventricular cavernomas are considered rare; however, an extremely unusual topography is the septum pellucidum, with only five reported cases in the English literature. These malformations may rupture and cause very large hematomas, leading to neurological impairment. Cavernomas can be familial or sporadic; additionally, these may appear following brain radiotherapy in extremely rare cases. CASE PRESENTATION: Herein, we present an extremely rare and unique case of a septum pellucidum cavernoma that occurred in a young male who had previously undergone brain radiotherapy in childhood due to acute lymphoid leukemia. Following presentation, he was diagnosed with generalized seizures. The cavernoma was resected via an anterior interhemispheric transcallosal approach, following which the patient remained stable without neurological sequelae. CONCLUSIONS: Ventricular cavernomas are rare lesions, especially when located at the septum pellucidum, thus constitute a challenging neurosurgical approach.