Abstract: In this paper, the heat transfer mechanism of micro-truss sandwich panel with channels was investi-gated. Based on some conservative assumptions, a simple and effective model for evaluating the thermal insulant performance of the sandwich panel was proposed. Meanwhile, a rapid method for evaluating the thermal insulant performance of the new integrative thermal protection structure with active cooling was established. The effectiveness and validity of this analysis model were verified by comparing with the detailed numerical simulation results provided by Fluent software. This study offers a support for the further application of the new structure.