Objective To investigate the clinical characteristics of bilateral medial medullary infarction (BMMI). Methods The clinical data, cranial magnetic resonance imaging (MRI) and prognosis at 3 months follow-up of 13 patients with BMMI were analyzed, retrospectively. Results The common symptoms and signs of BMMI were quadriplegia in 13 cases), dizzy in 10 cases, dysarthria in 8 cases, hypoglossal nerve palsy in 8 cases)and dyspnea in 3 severe cases. The disease had an acute onset with rapid progress and reached peak between day 3 and 6. There were ten cases with moderate to severe disability at 3 months follow-up. The risk factors were hypertension, hyperlipidemia and diabetes. MRI diffusion weighted imaging showed hyperintense signals in the bilateral medial medulla with classical "heart-"shape (6 cases) and "Y-" shape (6 cases). Magnetic resonance angiography showed unilateral vertebral artery stenosis or occlusion in most patients. Conclusion BMMI is a rare cerebrovascular disease with a poor outcome. MRI diffusion weighted imaging is of great value in the early diagnosis.