The thermal decomposition of sugarcane bagasse and cassava bagasse was investigated by the use of the non-isothermal thermogravimetric technique. The experiments were performed with the following heating rates: 5, 10, 15, 20 and 30 A degrees C min(-1). The kinetic parameters of thermal decomposition were estimated by the Flynn-Wall-Ozawa and the Kissinger methods. The results obtained for activation energy by the Flynn-Wall-Ozawa method were in the range of 126.62-148.80 kJ mol(-1) for the sugarcane bagasse and 157.64-227.74 kJ mol(-1) for the cassava bagasse, whereas the Kissinger method resulted in 124.54 kJ mol(-1) for the sugarcane bagasse and 144.31 kJ mol(-1) for the cassava bagasse. The pyrolysis of sugarcane bagasse occurred in the temperature range 270-480 A degrees C with average efficiency of 85.23 %, whereas the pyrolysis of cassava bagasse occurred in the range 270-540 A degrees C with average efficiency of 98.85 %. The experimental result for the high heating value was 16.103 MJ kg(-1) for sugarcane bagasse and 15.274 MJ kg(-1) for cassava bagasse, which means that these materials are suitable for use as alternative fuels.1251437445