Disposal of used automotive tires is a serious environmental problem. Among the available alternatives, pyrolysis offers the advantage of fuel production, both gas and liquid. The remaining char, consisting mainly of carbon-black, can hardly find any commercial use, but it could be used as raw material in solid fuel conversion technologies. In the present work, the reactivity of chars obtained by used tires pyrolysis is examined in a CO2 reacting atmosphere. Experiments were conducted in a bench-scale, fixed-bed tubular reactor. Char samples were prepared by pyrolysis of tires in a N2 atmosphere at 800°C. Gasification of chars with CO2 was carried out at temperatures between 800°C and 950°C. The extent of char conversion as a function of reaction time and temperature was determined. Used tire chars showed low reactivity during CO2 gasification at medium temperatures (800 – 850°C). However, by increasing gasification temperature at 900 – 950°C, conversion increased by 3 to 5 times. Based on the experimental results, gasification rates and kinetic parameters (pre-exponential factor and activation energy) were calculated, based on Arrhenious plots. The volume reaction model was found to be appropriate for correlation of the experimental data.