The invention discloses a fast reaction film formation method to prepare an eggshell type molybdenum carbide catalyst and belongs to the technical field of industrial catalysis. The method comprises the following steps: a carrier with a molybdenum oxide perssad adsorbed on the surface is added into a melamine solution, a film composed of a molybdenum carbide precursor is rapidly generated on the surface of the carrier through the fast reaction of melamine and the molybdenum oxide perssad, and the eggshell type molybdenum carbide catalyst is formed via pyrolysis of the film. According to the invention, the technology is simple, the thickness of the shell layer can be controlled, the energy consumption during the process is low, and the utilization rate and the stability of the active components in the prepared eggshell type molybdenum carbide catalyst are high and excellent. The eggshell type molybdenum carbide catalyst has excellent industrial application prospect and can be used for alkene-alkyne selective hydrogenation reaction and other reactions represented by phenylacetylene selective hydrogenation.