The present technology relates to a semiconductor memory device. The semiconductor memory device includes a plurality of channel plugs disposed in a cell region of a semiconductor substrate, a first dummy region and a second dummy region disposed at both end portions of the cell region, and first dummy plugs disposed in the first dummy region and second dummy plugs disposed in the second dummy region. A critical value of the first dummy plugs arranged in the first dummy region is different from a critical value of the second dummy plugs disposed in the second dummy region.