An experimental system for the simulation of total dissolved gas (TDG) supersaturated water was developed, which created the supersaturated water by increasing pressure of equilibrated water. Multiple levels of gas saturation can be obtained simultaneously by mixing supersaturated water and equilibrated water. Testing results of the system indicated that the system is capable of operating under designated temperature and providing TDG supersaturated water with stable levels ranging from 100% to 145%. It exists significant linear relationship between the level of TDG supersaturation and pressure. Testing results also showed that the system can be controlled and repeated,and used to study the theory and mechanism of the supersaturated water generation and the effects of high dams on downstream aquatic ecosystem.