The utility model provides a closed-shaped magnetic tunnel junction, which comprises a magnetic fixed layer, a magnetic free layer and a barrier layer arranged between the magnetic fixed layer and the magnetic free layer, wherein the magnetic free layer comprises at least one group of composite sub-layers; and the composite sub-layer is composed of a first magnetic layer, a nonmagnetic layer and a second magnetic layer. According to the utility model, the magnetic tunnel junction is internally provided with the magnetic free layer which comprises at least one group of composite sub-layers, the magnetic moment of the magnetic free layer and the magnetic moment of a reference layer are of a closed shape, and the magnetic free layer comprises at least one group of composite sub-layers, thereby being capable of eliminating stray magnetic fields between the layers and adjacent units, avoiding magnetic coupling interferences between the layers and the adjacent units, enhancing the shape anisotropy of the ferromagnetic coupling free layer, improving the thermal stability, reducing the critical current density, avoiding the structural and technological complexity caused by controlling the magnetization state by using an external magnetic field or a resultant magnetic field generated by high pulse current, and meeting requirements of large-scale productization.