Abstract In this research, a series of combustion experiments of Indonesian oil sands using a thermal analyzer were conducted at three heating rates (10, 20, and 50 °C min − 1 ) over the temperature range of 20–900 °C under atmospheric pressure. The obtained DTG curves revealed that combustion reactions occurred at three different stages in all the samples. The DTG peak, which is a measure of the relative reactivity, shifted to higher temperature with increasing heating rate. The ignition temperature was determined by using the TG-DTG extrapolation method, and the other principal combustion features, such as maximum weight loss rate, combustion release index and average quality reactivity, were all obtained. Simultaneously, an activation energy distribution method was employed to determine the combustion kinetics and then the relationship between the energy distribution E and the applicable volatile content/the total volatiles ratio V / V * was obtained by plotting the V / V * value against the corresponding E values. Furthermore, the ln k 0 vs. V / V * relationship was calculated. At the last, the ash composition of oil sands was determined by adopting the chemical analysis method.