The invention relates to a preparation method of ibuprofen sustained-release capsules and belongs to the field of medicine preparations. The method comprises the following steps: (1) adding a mesoporous material and polyethylene glycol into a solvent, and carrying out ultrasonic treatment; and (2) adding ibuprofen into a solvent system, stirring and volatilizing the solvent to obtain ibuprofen-loaded mesoporous particles, coating the mesoporous particles by using an organic macromolecule auxiliary material, crushing and sieving the obtained particles, and filling capsules with the particles to obtain the ibuprofen sustained-release capsules.