A mathematical model describing the thermal degradation of densified wood particles is presented. The influence of structural changes on the heat transfer properties of wood in its different stages is studied. The model uses a specific discretization scheme and combines intraparticle processes such as drying, pyrolysis and char heterogeneous reactions with extraparticle processes Such as heat and species diffusional and convective transport. The model also accounts for particle shrinkage. The model is used to compare the predicted data to data on the mass loss dynamic and internal temperature of several particles from the relevant literature, and a good agreement is found.