Abstract: The investigation progress on the thermodynamic characteristics of erbium hydride was introduced. In order to verify the thermal stability of erbium deuteride, the thermal desorption spectra (TDS) of erbium trideuterie were experimentally menstruated, and the corresponding relations of fine structure and TDS peaks of erbium deuteride were established. The deuterium release peaks of deuterium located at the octahedral interstice (β_Oct) and tetrahedral interstice (β_Tet) of facecentered cubic (fcc) framework of the fluorite-type lattice have been especially found. The activation energy of γ+β,β_Oct and β_Tet phases erbium deuteride decomposition were calculated from the Redhead’s thermal desorption model, and the calculated values are (178.3±3.0), (204.5±1.2) and (309.2±0.6) kJ/mol, respectively. The results show that phase structure has a significant influence on the thermal stability of erbium deuteride. A novel method to evaluate the impact of heating rate parameter on the thermal desorption characteristics of metal hydride is proposed. It is a method based on the thermal desorption experimental test and theoretical simulation using Redhead’s model. Using this method can greatly reduce the workload of the experiment.