The decomposition kinetics of three low density ablative materials are studied by means of TG. The method of Broido is applied to treat TGdata in order to obtain kinetic parameters from thermal analysis curves. By checking with CaCO
3 samples of known decomposition kinetic parameters, the results obtained are found to be in agreement with those from the literature, and differences in activation energy are less than 0.25%. The decomposition kinetic parameters of three low density ablative materials using the Broido method are obtained.