According to the wave characteristics of Dianchi lake,we build a wave propagation numerical model on the basis of the wave energy balance and wave action conservation equations.The model validation shows that the numerical results coordinates well with the ones by the empirical formula,and the numerical model is used to calculate the wind wave fields in the project area under the designed wind field before and after construction of the pier,which provides basic parameters for the schemes selection.The calculated results show that the north(N)wind wave has a great influence on the project while the WSW wind wave has less influence,and the L-shaped floating bridge has a better effect of blocking wave than the T-shaped one.