Thermal behavior of Harbul asphaltites (SE Anatolia, Turkey) has been studied using thermogravimetric analysis at atmospheric pressure and with nitrogen as the ambient gas. Asphaltite samples were ground and separated according to their size by sieving. Particle size distribution and chemical composition of asphaltite fractions are given. TG/DTG data of samples demonstrated two stages of mass loss. The first stage, called primary volatization, occurs in the range of 200-600 degrees C, and the second stage, called secondary gasification, in the range of 600-800 degrees C. Kinetic parameters of pyrolysis of asphaltite samples (activation energy, Arrhenius constant and reaction rate constant) were determined separately for both two stages using Coats-Redfern kinetic model.