Objective: To analyze the incidence and related factors of carotid and lower extremity artery plaque in type 2 diabetes mellitus. Methods: A total of 2 935 inpatients with type 2 diabetes mellitus were studied retrospectively. According to the results of carotid and lower extremity Doppler ultrasound, the patients were divided into three groups, including 655 patients without atherosclerotic plaques (group A); 1 044 cases of carotid or lower extremity atherosclerotic plaques (group B) and 1 236 cases of carotid and lower extremity atherosclerotic plaques (group C). The differences in clinical data and biochemical indicators between the three groups were compared, as well as the correlation between them and atherosclerotic plaques, and the prevalence of cardiovascular and cerebrovascular events among the three groups were compared. Results: The incidence of carotid and lower extremity artery plaque in diabetes mellitus was 77.7%, which was associated with age (OR=1.106, P<0.001), course of disease (OR=1.004, P<0.001) and sex (OR=0.338, P<0.001), BMI (OR=0.965, P=0.011). The prevalence of cardiovascular events (CVEs), cerebrovascular events (CBVEs) in group C was higher than that in group A. There was statistical significance (P<0.05). Conclusion: The prevalence of peripheral atherosclerotic plaques in patients with type 2 diabetes is high, and the risk of cardiac and brain events is significantly increased in patients with carotid and lower extremity artery plaques.