The calculation method of wave shoaling in the Code of Hydrology for Sea Harbour is still performed based on the linear wave theory,though the linear assumption is proved to be inaccurate in shallow water.In addition,the influences of external factors (e.g.wind and bottom friction) are not taken into account on the wave propagation.To compensate these drawbacks,a numerical model of wave shoaling is proposed based on the energy-conservation law and built under the cnoidal wave assumption.In this model,the shoaling calculation,considering wind and bottom friction effects,as two opposing ways of energy input and dissipation respectively,are taken into account.Based on the numerical model,a computational procedure is programmed.Using this procedure,a wide range of possible conditions is simulated.A practical calculation method (PCM) of wave shoaling for the preliminary engineering designs is proposed via studying the numerical results.