Considering the thermal protection of hypersonic vehicle and the power demand of airborne equipment, based on the optimization of engine energy management, an integrated system of high temperature power generation and high efficiency thermal protection was proposed with supercritical CO2 as the circulating working fluid combined with CO2 physical characteristics. This integrated scheme can provide electricity and reduce the fuel carrying capacity on the premise of achieving thermal protection purpose. The measures to improve the performance of the integrated system were put forward by analyzing the integrated system based on the fuel as the sole heat sink: to maximize the temperature of the fuel heated in the CO2cooler and improve the performance of the CO2 closed Brayton cycle by using regeneration. The thermal efficiency of the system can reach 17%. When the flight time was 30 minutes, compared with battery and fuel cell, the net mass gain of the integrated system was reduced by 85% and 68%, and the volume was reduced by 81% and 59%.