A kinetic study of olive oil pyrolysis has been carried out under different conditions by thermogravimetry. Nine TG runs were performed at nitrogen atmosphere, seven under dynamic conditions and two under dynamic+isothermal regime (constant heating rate until the set temperature was reached and then the set temperature was maintained constant). On the other hand, three dynamic runs were carried out with used olive oil.In addition, a study of the thermal decomposition was also carried out in dynamic runs at helium atmosphere using TG–MS and TG–IR at nitrogen atmosphere in order to observe the evolution of some compounds and to discuss the information that could be obtained.From the overall analysis of the data, a scheme of reactions was proposed and kinetic values were calculated by integration of the differential equations and minimizing the squared differences between the experimental and calculated values. An analysis of the influence of the initial mass on TG runs was performed on the assumption of vaporization processes.