Using AR mesophase pitch as precursor，the foaming process and its kinetic characteristic of mesophase pitch-derived carbon foam were studied by thermogravimetry，viscosity analysis，mass spectroscopy，and Fourier transform infrared spectroscopy. The results suggest that the aliphatic chains of pitch decomposed during foaming process，thus gases such as H2、CH4、H2O and CO were released，and the chemical structures of the pitch were changed，which led to the change of viscosity. In addition，the effect of heating rate and foaming temperature on foaming process of mesophase pitch was investigated based on thermogravimetric analysis，and it was found that mass loss （Δw） at a constant foaming temperature was proportional to a simple fractional exponent of foaming time （tb）. A simple mathematical model was proposed to describe the kinetics of isothermal foaming process for mesophase pitch with respect to heating rate effect by the Arrhenius equation，this research has a theoretical guidance for the controllable preparation of mesophase pitch-derived carbon foams.