The regulation of feeding behavior in animals are important for survival. The regulation of feeding behavior is a complex phenomenon involving the interaction of the central and peripheral nervous systems and neuroendocrine system. The aim of our research is to understand the evolutionary background of the neuropeptide-regulated system of feeding behavior in fish. Our studies revealed that not only feeding behavior but also psychomotor activity and/or emotional and reproductive behaviors are affected by several of neuropeptides. These results could provide insights into the role of instinct-regulating neuropeptides for vertebrates in general