Heat transfer experiments using various porous materials are performed to verify the possibility of extremely high heat flux removal (several dozens of MW/m2). The porous media introduced in this experiment are bronze particle-sintered ones and copper fibers-sintered ones that have high thermal conductivity, each of which can enhance the thermal diffusion in the porous material. From the heat transfer experiments using a non-transferred type of plasma arcjet as a high heat flux source, the steady heat removal of 66.0 MW/m2 is proved by using the bronze porous medium whose pore size and porosity are 100 μm and 0.38, respectively. Furthermore, as the result of evaluating the heat removal performance for various copper fiber porous media with the porosity from 0.5 to 0.7 and the fiber diameter from 30 to 90 μm, it is clarified that the maximum cooling performance exceeds 70.0 MW/m2 at the porosity of 0.7 and the fiber diameter of 90 μm, and that using the lower porosity material is useful for improving an evaporation rate in the porous media. Heat transfer experiments using various porous materials are performed to verify the possibility of extremely high heat flux removal (several dozens of MW / m2). The porous media introduced in this experiment are bronze particle-coated ones and copper fibers-sintered ones that have have high thermal heat, each of which can enhance the thermal diffusion experiments in a non-transferred type of plasma arcjet as a high heat flux source, the steady heat removal of 66.0 MW / m2 is proved by using the bronze porous medium whose porosity and porosity are 100 μm and 0.38, respectively. As the result of evaluating the heat removal performance for various copper fiber porous media with the porosity from 0.5 to 0.7 and the fiber diameter from 30 to 90 μm , it is clarified that the maximum cooling performance exceeds 70.0 MW / m2 at the porosity of 0.7 and the fiber diameter of 90 μm, and that using the lower porosity material is use ful for improving an evaporation rate in the porous media.