A drum washing machine including an improved balance weight mounting structure is disclosed. The drum washing machine includes a cabinet which forms an outer appearance of the drum washing machine, a tub disposed in the cabinet such that the tub is balanced in weight between positions opposing to each other on a front wall of the tub with respect to a center of the front wall of the tub, and a drum rotatably disposed in the tub to perform a washing function in accordance with a rotation of a motor attached to a rear wall of the tub. Balance weights are mounted to the front wall of the tub to cause the tub to be balanced in weight between positions opposing to each other on the front wall of the tub with respect to the center of the front wall of the tub.