The aim of this paper is to study the thermal degradation of waste tires (WT) by thermogravimetric analysis (TGA), for different heating rates, under nitrogen atmosphere (N2). Experiments were carried out at different heating rates to reach 800 °C. Kissinger–Akahira–Sunose (KAS) model was applied to calculate the kinetic parameters. Analyses were performed at the heating rates of 2, 10, 40 and 60 °C/min. The modelling developed here allows for the calculation of the solid temperature at different conversion degrees for different heating rates. Simulation of WT pyrolysis using ATG data showed a good agreement with experimental data for the KAS model. The dependence of the apparent Ea determined using the KAS model on the conversion rate reveals that pyrolysis progresses rather through multi-step kinetics.