The invention discloses a high-temperature-resistant aerogel composite material and a preparation method thereof. The preparation method includes the steps of (1) pretreatment of fibers, (2) preparation of silica alumina sol, (3) composite molding, and, (4) aging and drying; the obtained composite material has long-term resistance to the temperature of 1,000-1,300 DEG C, the 500 DEG C thermal conductivity is less than 0.06W/(mK), the density is 160-240kg/m<3>, and the 10% strain compressive strength is 0.5-0.9MPa. The high-temperature-resistant aerogel composite material and the preparation method thereof have the advantages that high-temperature-resistant fibers are subjected to heat treatment in advance to effectively remove impregnating compounds on the surfaces of the fibers, and accordingly, the composite control of the aerogel is facilitated; the silicon-aluminum composite aerogel with high temperature resistance can be obtained through control of the proportion of silicon to aluminum; the aerogel composite material resistant to 1,000-1,300 DEG C for a long time can be obtained through control of the contents of the aerogel and the fibers, and the application requirements forhigh temperature fields are met; the process is simple, the cost is low, and large-scale production is benefited.