A semiconductor storage device includes first high-potential wirings, second high-potential wirings, a first low-potential wiring, a second low-potential wiring, a first branch wiring, and a second branch wiring formed in a wiring layer between a memory cell array and a semiconductor substrate and each extending in a first direction. The first branch wiring is electrically connected to the first low-potential wiring, and is adjacent to the first low-potential wiring on one side in a second direction perpendicular to the first direction of the first low-potential wiring. The second branch wiring is electrically connected to the second low-potential wiring, and is adjacent to the second low-potential wiring on the other side in the second direction of the second low-potential wiring. A first via is provided to contact the first branch wiring, and a second via is provided to contact the second branch wiring.