Thermogravimetric analysis(TGA) was carried out for pyrolysis and char-CO2 gasification of low rank Indonesian ABK coal and China lignite. The pyrolysis rate was successfully described by a two-step model adopting the modified Kissinger method. The shrinking core model, when applied to char-CO2 gasification gave initial activation energy of 189.1 kJ/mol and 260.5 kJ/mol for the ABK coal and China lignite, respectively. Thus, the char-CO2 gasification has been successfully simulated by the shrinking core model. In particular, the activation energy of char-CO2 gasification calculated in this work is similar to the results on the anthracite coal, but considerable difference exists when other models or coal types are used.