To analyze the applicability of organic-inorganic composite grouting materials in high temperature environments, this paper prepared a two-component silicate modified polyurethane grouting material with water glass, glycerol, and catalyst as component A, and isocyanate, plasticizer, and flame retardant as component B. The effect of environmental temperature on the mechanical properties of the new grouting material was discussed, and the environmental temperature response law of the strength of silicate modified polyurethane slurry was studied. The quartz-sandstone was used as the grouting matrix material to perform cracks, new materials were reinforced by grouting, and the bonding characteristics of the slurry rock interface were analyzed through microscopic experiments. The results show that under the effect of high temperature environment, the strength and elastic modulus of silicate modified polyurethane slurry consolidated body show a decreasing trend. At 25 ℃, the compressive strength, tensile strength, compressive elastic modulus, and tensile elastic modulus of the slurry consolidated body reach 48.16, 15.47, 507.47, and 520.10 MPa, respectively. When the environmental temperature increases to 90 ℃, they decrease to 38.13, 9.63, 387.57, and 410.84 MPa, respectively. The material has low sensitivity to environmental temperature. The increase in environmental temperature disrupts the equilibrium of chemical reactions between the two components, reduces the degree of organic crosslinking solidification and the compactness of the consolidated body, resulting in a decrease in strength of the materials.