The brain serotonin (5-hydroxytryptamine, 5-HT) system is implicated in the neurobiological control of feeding and appears to be dysfunctional in patients suffering from feeding disorders, such as anorexia, bulimia, and obesity. Thanks to the identification and cloning of 5-HT receptors, the production of agonist and antagonist compounds, and the generation of 5-HT receptor knock-out mice, our knowledge on the implication of different 5-HT receptor subtypes in feeding behavior has greatly increased. A number of studies have demonstrated an involvement of the hypothalamic 5-HT 1B and 5-HT 2C receptors in food intake and body weight control, but the downstream events induced by such signaling remain to be explored. Moreover, little is known about the influence of 5-HT on the rewarding value of eating. Such value may not necessarily be linked to food consumption, but rather to voluntary reduction of food intake, as recently demonstrated upon activation of the 5-HT 4 receptors in the nucleus accumbens. Thus, abnormalities in the reward system in addition to those in the central control of the autonomic nervous system might contribute to the anorexic behavior. Recent studies have also reported an involvement of the 5-HT 6 and 5-HT 7 receptors in feeding behavior. Potential 5-HT receptor agonists/antagonists could then be developed and used in association with psychological treatment to better cope with the stressors that trigger anorexia and drug dependence.