Because of the well-characterized benefits of metabolic surgery for weight loss, glycemia, and metabolic status in patients, it has become widely used clinically. There are many surgical approaches, among which sleeve gastrectomy and Roux-en-Y gastric bypass are the most commonly used at present. However, because the precise mechanisms of their therapeutic effects are yet to be fully established, it is important to study the potential mechanisms of the effects of metabolic surgery using animal models. This review summarizes the characteristics of the animal models of metabolic surgery used in medical research and the information they have yielded regarding such mechanisms.