The invention belongs to the technical field of flue gas denitration and relates to a mixing method for cerium oxide and a molding agent. Cerium oxide is included, and the method further includes the following steps of A, first mixing, wherein in a shutdown state of a mixer, cerium oxide, ammonium metatungstate and stearic acid are placed into the mixer, and the mixer is started to rotate at low speed and then rotate at high speed after water is added; B, second mixing, wherein the mixer is stopped, kapok and glass fibers are added, and the mixer is started to rotate at high speed under exhaust; C, third mixing, wherein the mixer is stopped after rotating reversely at low speed for a period of time, CMC, PEO, 20% ammonium hydroxide and water are added, and the mixer is started to rotate reversely at high speed under exhaust; D, fourth mixing, wherein the mixer is stopped, CMC and PEO are added, and the mixer is started to rotate reversely at high speed under exhaust. The mixing method is uniform in mixing, enables cerium oxide and the molding agent to be fully mixed and facilitates preparation of a catalyst through molding.