The surface ablation of charring composites is critical for estimating the performance of the thermal protection system of a hypersonic vehicle during reentry. A coupled thermal/fluid/chemical/ablation method is proposed to solve the surface ablation of charring composites with the pyrolysis. Comparing to the previous method, it considers that the chemical reactions between the pyrolysis gases and the oxidative gases in the boundary layer have further influences on the oxidation of surface char in the Park's model. The new mathematical models are discretized by using the center and up-wind formats, and solved by the FORTRAN and MATLAB codes written. The numerical results indicate that the coupled method shows a validation in solving the surface ablation by comparing to the experimental data, and it can more accurately determine the surface recession rate of charring materials. This study will be helpful for the design of the thermal protection systems in hypersonic reentry vehicles. (C) 2017 Elsevier Ltd. All rights reserved.