In view of the complex internal structure of floating maintenance gates and the difficulty in calculating the stability of floating gates,the difficulty of quantity calculation and the complexity of drawings,etc.,combining with the application of the design of floating maintenance gate in Yakou hydro-junction in Hanjiang River,we adopt the BIM technology to explore the establishment of model,stability calculation and analysis,structure calculation,two-dimensional drawings generated,quantity calculation,checking and examination,application in construction stage and application in operation stage of floating maintenance gate.The results show that adopting the BIM technology,we can accurately calculate the floating stability of floating maintenance gates,greatly improve the efficiency of drawings and statistical engineering quantities of designers,and ensure the design quality.