A semiconductor memory device includes first and second memory chips, each including a region of a core circuit, a first area adjacent to a first side of the region in a first direction, a second area adjacent to a second side of the region in a second direction, a third area adjacent to the first area in the first direction and to the second area in the second direction, a first pad in the first area, a second pad in the second area, and third pad in the third area. In each memory chip, a first bonding wire connects the first and third pads. In addition, a second bonding wire connects the second pads of the first and second memory chips. The second memory chip is stacked on the first memory chip to expose the first, second, and third areas of the first memory chip in a third direction.