The invention discloses a preparation method of a green wallpaper adhesive. The preparation method comprises the following steps: preparing a premix A, preparing a tackifying auxiliary agent, and enabling the premix A, the tackifying auxiliary agent, natural glue juice, tripoli powder and an auxiliary agent to be subjected to a stirring reaction to obtain the green wallpaper adhesive. According tothe wallpaper adhesive disclosed by the invention, graphene is used as a base material, and the graphene is subjected to oxidation modification, so that the activity of the graphene is improved, andfurther the action force between the graphene and raw materials can be strengthened; besides, rare earth oxide, mica powder and layered hypophosphite are subjected to ultrasonic dispersion to be inserted into modified graphene, a formed system is stable in structure, further characteristics of adhesiveness, weather resistance and the like are strengthened, the added hydroxypropyl starch has the thickening effect, the added tackifying auxiliary agent effectively improves the caking property and the film formation property of the adhesive, construction of the adhesive is facilitated, and the tripoli powder can further promote mixing between the raw materials and strengthen the stabilizing effect of the system.