We report a case of trigeminal neuralgia caused by persistent trigeminal artery (PTA) associated with asymptomatic left temporal cavernoma. Our patient presented unstable blood hypertension and the pain of typical trigeminal neuralgia over the second and third divisions of the nerve in the right side of the face. The attacks were often precipitated during physical exertion. MRI and Angio-MRI revealed the persistent carotid basilar anastomosis and occasionally left parietal cavernoma. After drug treatment of blood hypertension, spontaneous recovery of neuralgia was observed and we planned surgical treatment of left temporal cavernoma.