A semiconductor memory device in which source lines for connecting source regions of memory cells disposed in a direction of word lines are composed of conductive films formed on a semiconductor substrate. Gate assemblies including components such as the word lines are formed on the semiconductor substrate. Source regions are formed in self-alignment by using the gate assemblies as masks. Source contact holes are formed above the source regions, and the source lines are in contact with the source regions in the source contact holes. The source lines are composed of conductive films formed on the semiconductor substrate between the adjacent word lines on opposite sides of any of the source regions.