Erbium was used as a model hydride-forming metal to study the possibility of applying thermal desorption spectroscopy (TDS) to research into hydride decomposition. The possibility of varying heating rates and final temperatures makes TDS acceptable for providing experimental information about the kinetics of decomposition. Discrimination of models and evaluation of rate constants were performed by fitting computer-simulation derived curves to experimental ones. The most probable models have boundary-value problems in which the rates of decomposition, desorption and migration of hydrogen are taken into account. The movement of an interface between hydride and solid solution of hydrogen is determined by all these reactions.