Objective To investigate the application of magnetic resonance angiography (MRI) in trigeminal neuralgia caused by vertebral-basilar artery compression. Methods Twenty cases of trigeminal neuralgia were diagnosed by MRI. MRI was utilized to diagnose the trigeminal nerve compression of the vertebral - basilar artery. Coronal sagittal reconstruction was performed by multiple sequence primal data, and the relationship between vertebral - basilar artery and the trigeminal nerve was observed. Relationship. Results The MRI diagnosis of 20 cases of vertebral - basilar artery compression of the trigeminal neuralgia. MVD surgery were found in the vertebral - basilar artery blood vessels, including the right vertebral artery in 4 cases, 8 cases of left vertebral artery, no bilateral Compression performance. Basilar artery in 6 cases, 2 cases of basilar artery abnormal branch of which 18 patients with vertebral - basilar artery were expanded> 4mm, an average of (4.9±3)mm, vertebral - basilar artery intracranial length (29.5±3) mm 5 cases with intracranial Lacunar ischemic changes. Conclusion Magnetic resonance imaging (MRI) is under a significant advantage in showing the anatomical morphology of the trigeminal nerve and clearly showing the change of the vertebral- basilar artery. It can greatly improve the detection rate of the spinal cord compression of the trigeminal nerve. The choice has the essential guidance significance.