Double barrier Magnetic tunnel junction (DBMTJ) is an attractive issue in the field of spintronics due to potential applications, such as spin diode , magnetic field sensor , and non-volatile spin-transfer-torque magnetic random access memories . Essentially, the DB structures give rise to a high spin filtering efficiency, thus not only enhancing the tunneling magnetoresistance (TMR) ratio but also improving the MR decay as raising bias voltage. Therefore, many efforts have been devoted to investigating the specific phenomena in DBMTJs  experimentally and theoretically. Comparing to the in-planed DBMTJ, however, the perpendicular-type DBMTJs have more potential in raising the operating speed and data density. Herein, we investigate the size effect and temperature dependent behavior of perpendicular-anisotropy magnetic tunnel junction embedded with iron nanoparticles.