Ghrelin has been recognized as an important regulator of growth hormone secretion and energy homeostasis. It is synthesized primarily by the stomach, and in substantially lower amounts by the bowel, pituitary, kidney, placenta, and hypothalamus. It is suggested that ghrelin contributes to the short- and long-term regulation of body weight as a key element of a complex central signaling network that regulates food intake and energy expenditure. Its levels increase preprandially and decrease after meals, suggesting a role in meal initiation. In this review, we summarize general features of the ghrelin hormone and results of studies done in childhood.