In the production of polymeric blends containing vulcanized rubber residues, the devulcanization (at least partially) is necessary so that, from the possibility of flowing as a result of the devulcanization process, the recycled elastomeric phase could present a high level of dispersion in the matrix. On the other hand, reactive processing (dynamic revulcanization) in blends composed of a thermoplastic phase and another highly concentrated elastomeric, provides the stability of the morphology, greater elasticity and results in improvements in the mechanical properties, thermal stability, among others. In the present work, as a way of recycling and revaluation of ground tire rubber (GTR), the influence of dynamic revulcanization of the GTR phase was analyzed in the dynamic-mechanical properties and morphology of blends composed of high-density polyethylene (HDPE)/GTR previously devulcanized by the action of microwaves. The results depicted the greater refinement of the morphologies of dynamically revulcanized blends, while the results of tan delta showed, mainly, modifications in the GTR phase as a result of the dynamic revulcanization of this phase during reactive processing.