The invention relates to the technical field of self-repairing anticorrosive paints and particularly relates to a self-repairing microcapsule used for a metal anticorrosive paint and a preparation method of the self-repairing microcapsule. The self-repairing microcapsule sequentially comprises a capsule core material and double layers of wall materials from inside to outside, a corrosion-inhibiting material is loaded between the double layers of wall materials, a coupling reagent is adhered on an outer wall of the double layers of wall materials, wherein the capsule core material is a reactant of a polyhydroxyl or multiamino compound and isocyanate, an inner wall of the double layers of wall materials is polyurethane, the outer wall of the double layers of wall materials is melamine formaldehyde resin, and the corrosion-inhibiting material is a nanoparticle and a metal corrosion inhibitor. The microcapsule is high in repairing efficiency, stable in mechanical property and simple in process, is matched with a matrix, has extensive applications, and can be widely applied to the fields of metal anti-corrosion and self-repairing materials like the petrochemical engineering, the marine industry and the automobile industry.