The invention discloses a multi-layer long-wall mining roadway arrangement method for an extremely-thick coal seam, is mainly used for solving the problems of high roadway tunneling quantity, high maintenance cost and the like if traditional roadway arrangement modes are adopted for mining of extremely-thick coal seams, and belongs to the technical field of coal mining. The method specifically includes the following steps that the extremely-thick coal seam is layered from top to bottom according to the certain thickness, stoping is performed on the layers in the descending sequence, an air return main roadway, an auxiliary transportation main roadway and a transportation main roadway are arranged along the bottom levels of a top layer, a middle layer and a bottom layer respectively, in-seam cross-cuts are dug from the three main roadways or inclined connection roadways for entering of the layers and digging of stoping roadways, and a production system is formed. The three main roadwaysare connected by the aid of the inclined connection roadways, a chute is dug in a centralized transportation roadway connected with section transportation drifts to be connected with a mining area coal bunker, and stoped coal is transported from the chute to the mining area coal bunker and is transported out through the transportation main roadway. With the method, the roadway tunneling quantityis low, efficient auxiliary transportation is facilitated, the resource recovery rate is high, and the method is safe and reliable.