With the development of large-scale wind turbines and floating offshore wind power，the service environment of wind power blades is becoming more and more complicated， and the damage and protection of blade leading edge are getting more and more attention. This paper briefly introduces the research on rain erosion damage in aviation，aerospace and wind power industries，taking“water hammer pressure”in solid/liquid impact process as the entry point. Commonly used rain erosion resistance test methods，such as single-jet method，rocket sled method and rotating arm method，are introduced. The improvement direction of rain erosion resistance test method is also proposed. The properties of several types of leading edge protective materials commonly used for blades are listed，and the difference in rain erosion resistance of leading edge coating materials under different sample preparation environments is compared. The selection and evaluation idea of leading edge protection materials is described，and the differentiated leading edge protection idea considering the rainfall situation in project area，blade linear speed and other factors is proposed.