The invention provides a fat coal based coal blending method. The method includes: carrying out coal petrography determination on single coal, and superimposing the coal petrography determination result, identifying the indicators of superimposed blended coal vitrinite reflectance layout to determine whether a coal blending scheme is reasonable and effective, and performing coking production according to the determined coal blending scheme, detecting the quality of the obtained coke, and evaluating the coal blending scheme according to coke hot index to determine the reasonableness of the coal blending scheme. Based on coal petrography coal blending, the method provided by the invention is a fat coal based low-cost coal blending method, has the characteristics of simple operation and easy implementation, etc. The coke produced by the method has good quality, can fully meet the large blast furnace coke demand, and realizes low-cost coal blending of enterprises.