Abstract: OBJECTIVE To analyze the clinical features of type 1 diabetes mellitus induced by nivolumab. METHODS Thirty cases of nivolumab-induced type 1 diabetes mellitus published before September 2019 were collected by retrieving PubMed, Web of Science, MEDLINE, CNKI, VIP and WangFang database, and then the data were analyzed statistically. RESULTS In the 30 cases, 16 cases were classified with fulminant type 1 diabetes mellitus and 18 cases developed ketoacidosis. The median occurrence time of nivolumab-induced type 1 diabetes mellitus was 87.5(37.5, 241.5)d, while the median interval of blood glucose change from normal to abnormal was 2(2, 4) weeks, the mainly clinical symptoms were polyuria and polydipsia(17 cases, 28.33%), different degrees of fatigue(14 cases, 23.33%), and nausea/vomiting(11 cases, 18.33%). The 27 patients were able to control their blood glucose after insulin therapy and 16 patients restarted nivolumab therapy. CONCLUSION Type 1 diabetes mellitus induced by nivolumab has the characteristics of dispersed incubation period, high complicated with ketoacidosis, and nivolumab can be restarted by actively blood glucose controlling. It is necessary to closely monitor patients' blood glucose routinely in the clinical application of nivolumab.