The present invention provides an environment-friendly, wear-resistant and highly weather-resistant polyurethane enamel and a preparation method thereof. The enamel includes the following components: Component A: water-based hydroxyacrylic resin, water-based polyurethane emulsion, hydroxymethyl cellulose, titanate coupling agent , Stabilizer, leveling agent, wetting and dispersing agent, emulsifier, pigment and filler, deionized water; component B: water-based hexamethylene diisocyanate trimer. The enamel is composed of two components, with water-based hydroxyacrylic resin, water-based polyurethane emulsion and hydroxymethyl cellulose as the main components of A component, and water-based hexamethylene diisocyanate trimer as B component, which can Effectively improve the hardness of enamel paint film, the composition design is reasonable, dilute with deionized water as solvent, instead of organic solvent, friendly to the environment, improve wear resistance, strong adhesion, good ductility, high temperature resistance, long service life, When coating, roller coating is used instead of spray coating, which can effectively improve the production environment and benefit the health of workers.