A semiconductor storage device includes a substrate and a memory cell array. The memory cell array is above the substrate in a first direction. The memory cell array includes first to third regions arranged in a second direction. The memory cell array comprises a first stack in the first and third regions, first and second semiconductor layers extending through the first stack in the first and third regions, respectively, a second stack in the second region, a first contact extending through the second stack, a fourth insulating layer extending in the first and second directions in the second region, and a fifth insulating layer extending in the first direction and a third direction in the second region. A distance from a bottom end of the fourth insulating layer to the substrate is different from a distance from a bottom end of the fifth insulating layer to the substrate.