The invention provides application of a supported heteropoly acid catalyst in preparation of a 9,9-bi(4-amido aryl) fluorene type compound. The supported heteropoly acid catalyst is prepared from heteropoly acid and a solid carrier, wherein the solid heteropoly acid is one or two kinds of materials from heteropoly acid such as phosphotungstic acid, phosphomolybdic acid, silicotungstic acid, silicomolybdic acid, germanotungtic acid or germanium molybdic acid; the carrier is one of materials from white clay, bentonite, kieselguhr, natural clay, silicon dioxide, aluminum oxide, molecular sieves,kaolin or active carbon. The application has the beneficial effects that the operation is simple and convenient; the reaction time is short; the yield is high; the catalyst can be repeatedly used formany times; the catalytic efficiency is improved; the production cost is also reduced; the environment pollution and the equipment corrosion are reduced; the application is applicable to industrial sustainable production.