The combustion characteristics of some biomass samples, such as rice straw and its cellulose, were investigated. Non-isothermal thermogravimetry, where the sample was heated in air and the temperature of which increased at a linear rate of 10°C/min, 20°C/min, 30°C/min, was used to investigate the combustion characteristics of the biomass samples. The differences in the TG-DTG-DSC curves of the samples were determined and discussed in detail. Conventional TG parameters, ignition index of samples were estimated which provided elaborate information on their basic combustion features. Results showed that cellulose with higher combustion characteristics.