Solid state decomposition of ammonia borane has been extensively reported to follow the Avrami-Erofe'ev equation. In this work, thermal analysis of ammonia borane is carried out under dynamic heating conditions under heating rate of 1-5 degrees C/min. The experimentally derived kinetic data is fitted against various solid state decomposition and autocatalytic kinetic models. It has been observed that the two steps of ammonia borane decomposition reactions follow different kinetics. The first step is more likely to be associated with the homogeneous autocatalytic reactions where the second part demonstrates the traditional nucleation growth kinetics. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.