Diabetes mellitus is a worldwide disease that leads to several acute complications including diabetic ketoacidosis, hyperosmolar hyperglycemia, and hypoglycemia. In addition, diabetes causes many chronic complications that lead to debilitation and diminished quality of life. Diabetic ketoacidosis is one of the serious acute complications; however, it is usually preceded by infection, acute myocardial infarction, stroke, or other dire events. Rarely does it accompany acute arterial thrombosis. Here, we report on a female patient who suffered from diabetic ketoacidosis combined with acute brachial artery thrombosis. After emergency treatment, including insulin therapy and surgical thrombectomy, the brachial artery was rescued and her prognosis was good.