Differential scanning calorimetry was used to study the thermal decomposition of 2,4-dinitrophenylhydrazine (DNPH) in isothermal regime. The DSC curves were carried out at several constant temperatures lower than the melting temperature. The standard isoconversional analysis of the obtained curves suggests an autocatalytic decomposition mechanism. This mechanism is also supported by the temperature dependence of the observed induction periods. (c) 2006 Elsevier B.V. All rights reserved.