Neuromedin S (NMS) was recently identified as an endogenous ligand for the FM-4/TGR-1 receptor in the rat hypothalamus. No previous studies have examined the effect of NMS on gut motility. We examined the effects of intracerebroventricular administration of NMS on food intake in food-deprived and free-feeding mice, and on gastroduodenal motility by using a manometric method, and gastric emptying in mice. We found that NMS decreased food intake and the gastric emptying rate. It also disrupted the motor activity in the antrum and duodenum of conscious food-deprived mice. These results suggest that NMS influences gut motility as well as feeding behavior.