In order to provide useful information for the sea levee protection under the background of global climate change, this paper gives a comprehensive review on the research of combined wave and surge overtopping. The latest research findings on overtopping discharge, flow characteristics on the inner slope, and turbulence features induced by combined wave and surge overtopping are summarized. It shows that the basic parameters of combined wave and surge overtopping can be estimated reasonably, based on which the flow equivalency among wave overtopping, surge overflow and combined wave and surge overtopping is discussed. It is pointed out that the different characteristic flow patterns between combined wave and surge overtopping and wave overtopping, as well as their impacts on levees need to be investigated so as to provide better references for the design, assessment and reinforcement of levees.