Obesity is one of the major public health problems in the world. While various methods have been investigated or introduced, bariatric surgical procedures are currently the only effective long-term therapies for treating obesity. Due to mortality and morbidity, the bariatric surgery is limited to a subset of patients with morbid obesity. In this chapter we present an overview of an emerging anti-obesity therapy: gastric electrical stimulation (GES). First, the scientific basis for GES as a potential therapy for obesity is introduced. Secondly, GES methodologies and configurations are presented. Methods of GES that have been used for treating obesity are then introduced, and their effects on food intake and body weight are presented, followed with the discussion on possible mechanical, neural and hormonal mechanisms involved in the anti-obesity effect of GES. Finally, our viewpoint on the potential of GES for obesity and future development of the GES therapy are provided.