Nitric oxide is one of essential regulators of the physiological functions of the gastrointestinal tract including vascular tone, transfer of nerve impulses, protection of mucous coats, motor activity and secretion. The review of literature presents data on sources of nitric oxide, its molecular and cellular interaction, role in the genesis of different diseases of the gastrointestinal tract. The experimental and clinical material provides grounds for approaches to the regulation of this signaling pathway with the help of nitric oxide donors, activators and inhibitors of its formation, arginine, antioxidants, phosphodiesterase and guanylate cyclase inhibitors. The bibliography includes 93 references.