China has made remarkable achievements in the management of severe mental disorders，but there are only a few research reports on the risk of diabetes in severe mental disorders. Foreign studies have shown that the risk of diabetes increases the most in patients with severe mental disorders. Blood glucose control in this population has become a new direction of work and research. The study found that the detection rate of diabetes among hospitalized patients with severe mental disorders in the Second People’s Hospital of Jiangning District，Nanjing，was 20.1%. Variables such as mental illness type，age，course of disease，sex and marital status were essential factors for comorbid diabetes. It is called for diabetes screening in hospitalized patients with mental illness should be carried out as soon as possible，to explore possible influencing factors，and conduct timely evidence-based research to focus on patients’mood and increase their exercise level to control their blood glucose level，so as to reduce the risk of diabetes.