Methods of manufacturing a magnetic memory device including forming a lower magnetic layer, a tunnel barrier layer, and an upper magnetic layer on a substrate, forming a magnetic tunnel junction (MTJ) pattern by patterning the lower magnetic layer, the tunnel barrier layer, and the upper magnetic layer, forming a first insulating layer exposing an upper surface of the MTJ pattern, forming a polymer pattern on the exposed upper surface of the MTJ pattern, forming a second insulating layer exposing an upper surface of the polymer pattern, removing the polymer pattern to form a cavity in the second insulating layer, the cavity exposing the upper surface of the MTJ pattern, and forming a metal line by filling the cavity with a conductive metal.