The invention provides a rain season foundation pit earth rapid construction method. The method comprises that before foundation pit earth excavation construction is carried out, and after the completion of positioning, line releasing and reference point guiding and measuring work, the foundation pit outer slope and the driving route are paved, and the construction of a water intercepting brick wall, a drainage groove, a water collecting pit and other drainage facilities are carried out; and corresponding reinforcing and drainage corresponding measures are carried out during the foundation pitearth excavation construction. According to the rain season foundation pit earth rapid construction method, the foundation pit rain period pre-protection is carried out through the excavation early-stage simple work preparation, the possibility that rainwater outside the foundation pit flows into the foundation pit is completely eradicated, the drainage pressure of the foundation pit is reduced,the rainfall period of the foundation pit is shortened, and rapid construction of the the foundation pit earth in the rainy season is realized; and the drainage construction scheme which is stopped inthe rain season is provided, and construction safety hazards caused by improper drainage in the rain season are reduced.