Diabetes mellitus (DM) has become a worldwide epidemic, with an increasing incidence year by year. To further explore the pathogenesis of DM and develop more effective prevention and treatment programs, researchers need stable, replicable animal models that are similar to human diseases. The administration of streptozotocin ( STZ) has been used for half a century to induce DM, and is the most widely used method for establishing animal models of DM in basic research. In this paper, the main factors influencing STZ-induced DM rat models are briefly reviewed. On the basis of the research result and related literature, some suggestions for the future preparation of STZ-induced DM rat models are made.