OBJECTIVE To provide reference for the safe use of bevacizumab in cancer patients. METHODS The diagnosis and treatment of a 65-year-old female lung adenocarcinoma patient with diabetic ketoacidosis (DKA) induced by bevacizumab was retrospectively analyzed, and the possible mechanisms and causes were analyzed based on literature review. RESULTS & CONCLUSIONS The diagnosis and treatment process of patients were analyzed, and DKA caused by other drugs and disease factors were excluded. DKA was considered to be caused by the use of bevacizumab according to Naranjo’s ADR evaluation scale; the acidosis of the patient improved rapidly after one hemodialysis treatment. DKA caused by bevacizumab is rare in clinic, clinicians should be aware that bevacizumab may affect pancreatic function and induce DKA, and early detection and treatment should be achieved to improve the prognosis.