Abstract: This is the first report on the experimental results about the aerothermal environment of high temperature jet flow (HTJF) and its interaction flow. The significance of this experiment is to abstract the physical mode from the real flight of hypersonic aircraft in order to provide experimental evidence for the thermal protection requirements. This experiment used the compression corner as the research object to research the aerothermal environment influenced by the HTJF and the interaction flow by the HTJF in combine with the main flow filed. In this paper, the main flow came from the impulse wind tunnel; the HTJF came from the high enthalpy gas supply platform, which used the ox-hydrogen burner to drive the Ludwieg tube. This paper used the pressure change of the driven section in the impulse wind tunnel to control the producing of the HTJF in order to assure the synchronous operation of the two parts of flow. This paper will present the research about: (1) To standardize the thermodynamic state of the HTJF; (2)The experimental research of the compress corner which include three experimental status: (i) the aerothermal environment in the main flow without the HTJF; (ii) the aerothermal environment in the high temperature jet flow without the main flow; (iii) the aerothermal environment in both the high temperature jet flow and the main flow. It is found from the experiment that the aerothermal environment of the part of the compress corner has great influenced by the high temperature gas flow. The high temperature gas jet flow can cause the heat flux peak an order of magnitude than the heat flux peak without it.