The invention discloses a polyurethane rigid foamed plastic composite material with inorganic particles modified by coupling agents. The inorganic particles are inorganic nanometer particles or inorganic micrometer particles, and the coupling agents include at least one type of silane coupling agents and titanate coupling agents. The polyurethane rigid foamed plastic composite material is particularly prepared from foaming material compositions. The foaming material compositions comprise composition polyol, the inorganic particles, the coupling agents, surfactants, foaming agents and isocyanate. The invention further discloses a method for preparing the polyurethane rigid foamed plastic composite material and application of the polyurethane rigid foamed plastic composite material. The polyurethane rigid foamed plastic composite material, the method and the application have the advantages that the incompatibility of the inorganic particles and the polyol which is a raw material is utilized, the inorganic particles and the polyol are used as heterogeneous nucleating agents in foaming procedures, and accordingly foam holes can be reduced; effects of reinforcing polyurethane rigid foamcan be realized by the inorganic particles, and accordingly the structure rigidity and the dimensional stability of the polyurethane rigid foam can be improved.