The invention provides an etoxazole preparation method. The etoxazole preparation method comprises the step: enabling a compound as shown in a formula I to react with ammonia gas or an ammonium solution, thus generating etoxazole. The preparation method provided by the invention is simple in technology ad good in reaction selectivity, generation of etoxazole isomer impurities can be reduced to a large extent, the reaction yield is up to 87 to 95 percent, the product content is up to 95 to 97 percent, a byproduct just comprises ammonium chloride, and the content of the ammonium chloride is 99 percent or more, thus meeting the national standard requirements of industrial ammonium chloride; meanwhile, by adopting the ammonia gas or an aminomethanol solution, water can be prevented from beingintroduced in a reaction system, so that a rectifying and separating process of an organic solvent and the water during solvent recovery can be omitted, the cost and the energy consumption of production equipment are reduced, the etoxazole preparation method is suitable for industrial production, and higher economic benefit can be generated.