Objective To investigate the characteristics of vascular lesions in patients with newly diagnosed diabetic cerebral infarction.Methods Related clinical data were collected from 4 172 patients with acute cerebral infarction who were admitted to Department of Neurology， Songjiang Hospital Affiliated to Shanghai Jiao Tong University School of Medicine， from January 2017 to June 2024. Among whom 716 patients with diabetes were divided into newly diagnosed diabetic cerebral infarction group with 359 patients and cerebral infarction+diabetes history group with 357 patients. The patients in both groups were measured in terms of random blood glucose， glycated hemoglobin， glycated albumin， fructosamine， creatinine， total cholesterol， triglyceride， high-density lipoprotein cholesterol， low-density lipoprotein cholesterol， and homocysteine， and all patients underwent cranial magnetic resonance imaging， magnetic resonance angiography， CT angiography. And whole brain angiography.Results Compared with the cerebral infarction+diabetes history group， the newly diagnosed diabetic cerebral infarction group had significantly lower number of symptomatic cerebral infarction attacks （P=0.002） and levels of blood glucose （P=0.001） and creatinine （P=0.044）. Compared with the cerebral infarction+diabetes history group， the newly diagnosed diabetic cerebral infarction group had a significantly higher proportion of patients with precirculating cerebral infarction （P = 0.016） and a significantly lower proportion of patients with postcirculating cerebral infarction （P=0.002）， as well as a significantly higher proportion of patients with multiple cerebral infarction （P=0.002） or multiple vascular stenosis （P=0.005）. Compared with the cerebral infarction+diabetes history group， the newly diagnosed diabetic cerebral infarction group had a significantly higher total number of intracranial blood vessels with stenosis or occlusion （P<0.001）， as well as a significantly higher number of blood vessels with stenosis or occlusion in the anterior circulation （P<0.001）， the middle cerebral artery （P<0.001）， the extracranial segment of the internal carotid artery （P=0.004）， and the extracranial arteries （P=0.006）. The multivariate logistic regression analysis showed that multiple vascular stenosis （P=0.045）， multiple cerebral infarction （P=0.030）， middle cerebral artery stenosis or occlusion （P=0.031）， and posterior circulation infarction （P=0.001） were influencing factors for newly diagnosed diabetic cerebral infarction.Conclusions Some patients with newly diagnosed diabetes may have cerebral infarction as the initial manifestation， and compared with the cerebral infarction patients with a long history of diabetes， such patients may have multiple sites involved in infarction and an increasing number of blood vessels with stenosis or occlusion， especially in the middle cerebral artery， with a relatively low proportion of patients with posterior circulation infarction. ［Journal of International Neurology and Neurosurgery, 2024, 51(4): 8-15］