Abstract: A hybrid method (MCHF method) combined the Monte-Carlo method and the heat flux method was presented to analyze radiative heat transfer in a three-dimensional enclosed rectangular. The special heat flux parameter distribution and the temperature distribution of the rectangular were analyzed by comparing the computational results with exact results by the classical zone method. The analysis showed that the results calculated by the MCHF method are reasonable with excellent accuracy and efficiency, thus the MCHF method has a strong application value in radiative heat transfer in industrial furnaces.