Provided herein are methods of fabricating a magnetic memory device including forming magnetic tunnel junction patterns on a substrate, forming an interlayered insulating layer on the substrate to cover the magnetic tunnel junction patterns, forming a conductive layer on the interlayered insulating layer, patterning the conductive layer to form interconnection patterns electrically connected to the magnetic tunnel junction patterns, and performing a cleaning process on the interconnection patterns. The cleaning process is performed using a gas mixture of a first gas and a second gas. The first gas contains a hydrogen element (H), and the second gas contains a source gas different from that of the first gas.