Corticotropin releasing factor (CRF) family peptides have an important role in the control of food intake. We investigated the effects of CRF family peptides on food intake and body weight gain in mice. Of the CRF family peptides, including CRF, urocortin1 (Ucn1), urocortin2 (Ucn2) and urocortin3 (Ucn3), peripherally administered Ucn1 was shown to have the most potent inhibitory effect on the food intake and body weight gain of both lean and high fat fed obese mice. In addition, repeated administration of Ucn1 lowered blood glucose and acylated ghrelin, and decreased the visceral fat weight of high fat fed obese mice.