This chapter is presenting an overview of data mining and machine learning models devoted to different aspects of diabetes during the last two decades. Thirty-six machine learning models have been used by 31 authors for different aspects of diabetes, including prediction, diagnosis, classification and complications of diabetes. Table 5.1 summarizes the different algorithms used with at least one reference for readers who need to know how these algorithms are defined and implemented. Table 5.8 lists 30 authors with the names of the algorithms implemented, the data for training and testing these algorithms and the algorithm giving the best accuracy.