Abstract This work analyzes the thermal decomposition kinetics of sacha inchi shells (SIS) to understand the reactions involved in the energy use of this residue and upgrade this biomass into solid fuel. Thermogravimetric analyses were carried out using 50 ml/min of synthetic air, a mean particle diameter of 0.150 mm, and heating rates of 2.5, 5, and 10 °C/min from 25 to 700 °C. Also, the ignition, peak, and burnout temperatures, ignition index, and comprehensive combustibility index indicate that the reactivity of the SIS is higher than several biomasses. In addition, the activation energy for the global reaction mechanism was 161.90 ± 49.90 kJ/mol and 133.94 ± 36.58 kJ/mol applying the Friedman and Vyazovkin methods. The activation energies were 100, 160, 150, 80, 100, and 100 kJ/mol for a scheme of six independent parallel reactions. Finally, through the thermal decomposition and physical-chemical properties, it is concluded that SIS is a potential resource of thermal energy.