The Ge2Sb2Te5 compound is of interest for applications in phase change non-volatile memories. First-principles calculations of phonon dispersion relations and electron-phonon coupling constant provide an estimate of the electron-phonon contribution to the thermal boundary resistance at the interfaces of Ge2Sb2Te5 with dielectrics (silica) and metal electrodes (Al and TiN). The diffuse mismatch model including full phononic dispersion has been used to compute the phononic contribution to the thermal boundary resistance. The calculated value of the electron-phonon contribution to the TBR at 300 K of about 14 m(2)K GW(-1) would dominate the TBR at the interfaces of hexagonal Ge2Sb2Te5 with the surrounding dielectrics and metals considered here once interdiffusion at the boundaries could be minimized.