Abstract: In the aero-dynamic environment,optical windows shape and optical property will be changed because of high heat flow,then the employment of the transmission of optical windows will be effected.According to the requirement of IR imaging technique applied in hypersonic aircraft,the heat transfer characteristic in optical windows under aerodynamic heating were studied and the three dimensions unsteady state heat conduction equations in unstructured were established.The effect of initiative cooling and passive heat insulation thermal protection technology were calculated with the engineering prediction software-Fluent.The feasibility of initiative cooling technology on temperature control of optical windows were validated.The capacity were caculate and some computer simulation results at classical state were presented.