A gun hanger for vertically hanging a firearm is disclosed. The gun hanger allows an operator to hang the firearm in a vertical position to enable the operator to use both hands for other tasks, such as climbing over a fence or climbing a tree, thus increasing firearm safety. In one embodiment, the gun hanger comprises an L-shaped member and a flat plate member. The flat plate member has a recess sized to accept the magazine of a firearm and secure the gun hanger to the firearm with the magazine cap. The recess can be sized to accept different firearms such as 12 gauge and 20 gauge shotguns. The L-shaped member can be mounted on many surfaces such as fences, tree branches, and boat sides to keep the firearm in a vertical position. Methods for using the gun hanger are also disclosed.