A method of forming a line a semiconductor device, including the steps of forming an interlayer insulating film on a semiconductor substrate in which predetermined structures are formed, forming a trench through which a predetermined region of the semiconductor substrate is exposed in the interlayer insulating film, sequentially forming a glue layer and a first barrier metal film on the entire surface including the trench, forming a second barrier metal film at the bottom of the trench, and forming a line within the trench.