Plunging breaking waves generate turbulence and vorticity, which are of great importance for the solute and sediment transport in surf zone. In this paper the complex breaking processes are simulated by using an accurate numerical model that solves the Reynolds equations for the mean flow and modified k-&egr; equations for the turbulence field. A solute transport model is employed to investigate the solute mixing under plunging waves. After validation of the numerical model by comparing numerical results with available experimental data, the numerical model is further utilized to study the detailed mechanisms of turbulence transport and vorticity dynamics. The differences between spilling and plunging breaking waves are discussed. The impact of the wave breaking on solute mixing in the surf zone is also examined. ¿ 1998 American Geophysical Union