Abstract: A fireproof laminate passing Grade 2 incombustibility according to Japanese Industrial Standard (JIS) A-1321 combustion test is disclosed. The laminate comprises a urethane modified polyisocyanurate foam as a core material and an aluminum foil with a thickness of not less than 0.015 mm as a front surface material piled on the foam through self-adhesion of the foam. When the foam is produced by reacting an organic polyisocyanate with polyols as a modifier in the presence of an isocyanate trimerization catalyst, a blowing agent and other additives, a combination of particular low molecular weight diols with particular high molecular weight polyols is used as the polyol in a special weight ratio and a special total amount per 100 parts by weight of the organic polyisocyanate.