Objective:To investigate the clinical characteristics, imaging features, treatment, prognosis, and possible causes of myelodysplastic syndrome complicated by acute cerebral infarction.Methods:The clinical data of four patients with myelodysplastic syndrome complicated by acute cerebral infarction who received treatment at Peking University International Hospital and Beijing Jingcheng Boai Hospital from January to December 2021 were retrospectively analyzed.Results:All four patients experienced myelodysplastic syndrome complicated by acute cerebral infarction for the first time. They were aged 60-69 years, with a median age of 65 years. Bone marrow suppression occurred in the four patients with myelodysplastic syndrome after chemotherapy, resulting in a remarkable reduction in the number of platelets. All four patients had just been transfused with platelets before the onset of myelodysplastic syndrome complicated by acute cerebral infarction. The main clinical manifestations were dyskinesia, language disorder, paresthesia, and dizziness. Three patients had multiple foci, two of them involved bilateral cerebral hemispheres, and only one patient had a single focus. Circulation improvement and symptomatic treatment were given after admission. Two patients with cerebral hernia died, and two patients were discharged after improvement.Conclusion:The pathogenesis of myelodysplastic syndrome complicated by acute cerebral infarction is complex. It includes many causes rather than common risk factors for stroke. Myelodysplastic syndrome complicated by acute cerebral infarction is rare in the clinic. It is difficult to treat, is serious, and has a poor prognosis.