One of the most important health problems in the world is obesity, due to its relationship with numerous illnesses such as diabetes mellitus type 2, hypertension and the increased risk of cardiovascular disease. The basis of treatment is diet and physical activity, but in some cases, this is not enough and it has to be combined with a pharmacological treatment. Recently, sibutramine was withdrawn from the market, so orlistat is the only medication that is suitable for this therapy; however orlistat is not without contraindications or side effects. Owing to this situation, phytotherapy treatments are being taken up again. Nevertheless, in some cases there are several doubts. In this review, we intend to provide the necessary information regarding the main plants that are used in the treatment of obesity.