The invention belongs to the technical field of high polymer materials, supramolecular materials and adhesives, and particularly relates to an epoxy resin hot melt adhesive and a preparation method thereof. The epoxy resin hot melt adhesive material is prepared from epoxy resin, polyether amine and a polyether amine ureido pyrimidone derivative, wherein under a high-temperature condition, UPy is dissociated, and the hot melt adhesive flows to infiltrate the surface of an adhered object, and under a low-temperature condition, UPy is associated, the hot melt adhesive is cured, and the adhered objects are adhered together. According to the invention, the epoxy resin hot melt adhesive based on UPy has the advantages of repeatable bonding, high bonding strength, wide bonding range, high bonding speed, low bonding temperature, adjustable bonding strength, environment friendliness and the like; the prepared epoxy resin hot melt adhesive is simple in structure and wide in raw material source; in the preparation process of the epoxy resin hot melt adhesive, no solvent is used, the solid content of the hot melt adhesive is 100%, and the epoxy resin hot melt adhesive is an environment-friendly adhesive; and the process is simple, no by-product is generated, no waste is discharged, and the atom utilization rate is 100%.