The invention discloses a drainage system of a clothes dryer and the clothes dryer with the drainage system. The drainage system comprises a condensate water container, a drainage pump, a drainage pipe and a water accumulation container. A condensate water cavity is defined in the condensate water container and provided with a condensate water inlet communicated with a condensate water outlet of the clothes dryer. One end of the drainage pump is connected with the condensate water container. A drainage opening is formed in one end of the drainage pipe. The water accumulation container is connected between the other end of the drainage pump and the other end of the drainage pipe. In the vertical direction, the highest point of an outlet of the water accumulation container is lower than the lowest point of an inlet of the water accumulation container and one part of the drainage pipe, and the lowest point of the outlet is not higher than the drainage pipe. According to the drainage system in the embodiment, condensate water is easy to drain, the drainage performance is good, and the drainage noise is low.