A magnetic memory device includes a substrate, a circuit device on the substrate, a lower electrode electrically connected to the circuit device, a magnetic tunnel junction structure (MTJ structure) on the lower electrode, and an upper electrode on the MTJ structure. The MTJ structure includes a pinned layer structure including at least one crystalline ferromagnetic layer and at least one amorphous ferromagnetic layer, a free layer, and a tunnel barrier layer between the pinned layer structure and the free layer.