The foundation bed leveling for the second phase of Yizheng waterway regulation project of the deep-water channel 12.5 m below the Yangtze River of Nanjing is characterized by deepwater,large flow velocity,low visibility and small amount.The existing bed leveling methods cannot meet the construction requirements.We develop the underwater bed automatic leveling equipment.Through the design of general structure,the development of automatic leveling control system,the research of automatic leveling construction process and the application of practical project,the equipment realizes underwater bed automatic leveling construction in the complex hydrological environment.This equipment is characterized by high leveling accuracy,high construction efficiency,low cost and broad application prospects.