The oxidation reaction of tobacco char plays a key role in the cigarette burning process. The knowledge of the intrinsic oxidation reactivity of tobacco char is important for the control and optimization of the combustion process. In cigarette smoking the heating rate of tobacco can vary from 10 to 500 oC/second. The influence of heating rate on the intrinsic oxidation reactivity of tobacco char is unclear. Bright tobacco was pyrolyzed at 500 oC under helium for a variety of holding times in a tube furnace (slow heating rate) and a grid screen heater (fast heating rate). The morphology of tobacco chars was examined by scanning electron microscopy (SEM) and the surface area determined by vapor phase adsorption technique. The chars prepared with a fast heating rate appeared to have undergone a plastic stage during pyrolysis. The oxidation reactivity of the chars in various concentrations of oxygen in helium was characterized by two isothermal thermogravimetric methods (with or without exposure to partial oxygen atmosphere during the heating ramp). The char oxidation process is described by a first-order global reaction and the heterogeneous reaction kinetic parameters were calculated. Our results also showed that the effect of heating rate to the char oxidation reactivity was relatively small. The oxidation reaction rates of chars exposed to the partial oxygen atmosphere during the heating ramp were lower than those heated up to the target temperature in helium.