Abstract: A memory device includes a word line including a cell array region and a connection region extending in a first direction from the cell array region; a first select line and a second select line, spaced apart from each other in a second direction intersecting the first direction on the cell array region, the first select line and the second select line, extending onto the connection region of the word line; and an isolation pattern disposed between the first select line and the second select line. The isolation pattern includes a first sub-isolation pattern extending in the first direction and a second sub-isolation pattern extending in the second direction from the first sub-isolation pattern. The second select line is bent to surround an outside corner defined at an intersection point of the first sub-isolation pattern and the second sub-isolation pattern of the isolation pattern.