The invention discloses an environment-friendly wall decoration fireproof coating, comprising ceramic fiber, vermiculite, perlite, fine asbestos, borax, mica powder, aliphatic waterborne polyurethane, a film-forming agent, a foaming agent and deionized water, wherein the foaming agent consists of a thermoplastic acrylic resin type polymer, sodium dodecyl benzene sulfonate, ammonium borate, ammonium polyphosphate and deionized water. The raw materials for preparing the coating disclosed by the invention are environment-friendly, have good fireproof performance, cannot deform easily, are high in strength, and cannot fall off and bulk; and preferably, the foaming agent is environment-friendly and nontoxic and has a reasonable formula, so that in the case of fire, the foaming agent expands to generate foams quickly to form a compact sponge-shaped expansion foam layer with a good heat-insulating property, combustible base materials can be protected more effectively, black smoke cannot be generated, and the concentration of organic volatiles is extremely low, which is beneficial for the health of sufferers and rescuers in the fire disaster. The preparation method disclosed by the invention is simple and is easy to operate, and the environment-friendly wall decoration fireproof coating is convenient in construction and firm in adhesion, and cannot crack to ensure that a wall body has a long service life.