The invention discloses a rapid quantitative evaluation method of a rock weathering degree and an application thereof. The method comprises the following steps: testing a fresh rock rebound value anda rock rebound value, calculating an attenuation rebound index, according to the measured different cave depth rock rebound values, the rock attenuation rebound index, and the structural surface attenuation rebound index, making a rebound characteristic change chart along a measuring line, performing a rock rebound value characteristic analysis of different weathering bands, dividing the weathering bands according to the determined rebound characteristic values of the different weathering bands, and performing quantitative determination of the rock weathering degree. The rock weathering degreeis subjected to quantitative determination by the rock rebound value and the change rate measured by a resiliometer, the quantification dividing of the rock weathering band is carried out, the measured index pertinency is strong, the measurement method is simple, the data processing is easy, cost is low, the speed is fast, normal construction is not interfered, and the evaluation method has wideapplication prospect in the fields of rock weathering degree quantitative evaluation of slope, dam foundation, and cave surrounding rocks in mountain area large-scale water power engineering and traffic engineering.