The invention relates to a method for preparing corresponding diacid by cyclone oxide, and is characterized in that a composition composed of a titanium-silicon molecular sieve and multiple-metal oxyacid or a salt thereof are taken as a catalyst, under the temperature of 10 DEG C-160 DEG C and the pressure of 0.1-2.0 MPa, cyclic ketones, hydrogen peroxide, a solvent and the catalyst are reacted according to a mol ratio of 1: 0.1-10 of cyclic ketones to hydrogen peroxide, a mass ratio of 1-1000:1 of solvent to catalyst and a mass ratio of 1-100:1 of cyclic ketones to catalyst. The method has the advantages of high conversion rate of cyclic ketones, good selectivity of corresponding diacid, good catalytic activity and stability. The preparation method is an environment-friendly synthetic process, and has a simple production process which is suitable for industrial production and application.