Objective To study the clinical manifestations,etiology,magnetic resonance imaging features,prognosis of patients with bilateral medial medullary infarction.Methods The clinical information of two case reports were summarized with review of the literature.Results The 2 patients with bilateral medial medullary infarction reported here were manifested with progressive quadriplegia,both complicated with respiratory disorders.On etiology,both were due to atherosclerosis,and one was combined with congenital vascular variation.The Y shaped hyperintense signals were seen in diffusion weighted imaging (DWI) cross-section in the medulla oblongata level.And both had poor outcomes that one was dead and the other was discharged with tracheotomy and severe sequela.Conclusions Bilateral medial medullary infarction is presented with complicated symptoms such as quadriplegia,dysarthria,hypoglossoplegia,even respiratory failure,in which quadriplegia is most often seen,and it is associated with a poor clinical prognosis.DWI appears the characteristic Y Shaped sign.