The invention provides a polyurethane mixed component cured after high temperature, and belongs to the technical field of polyurethane materials. The mixed component is prepared from, by weight, 40-60parts of a polyurethane prepolymer, 20-30 parts of modified kieselguhr, 4-8 parts of aqueous polyisocyanate and 3-5 parts of auxiliaries. The polyurethane prepolymer is obtained after a reaction of polyether polyol, diisocyanate, a chain extender and a catalyst; the modified kieselguhr is obtained by performing surface modification on kieselguhr through a mixture of 2(ethylacetoacetate)aluminic isopropyl ester and gamma-methyl propyl trimethoxy silane. Due to cooperation of the polyurethane prepolymer, the modified kieselguhr and aqueous polyisocyanate, no bubble is generated on the surface of the obtained composition, and due to the fact that the modified kieselguhr can modify the interface effect between modified substances, the bonding performance of the polyurethane material is improved.