A semiconductor memory device including a memory cell array, a first row decoder adjacent the memory cell array, and a second row decoder adjacent the memory cell array. A memory cell array may include first and second memory cell blocks on respective first and second semiconductor layers. The first memory cell block may include a first word line coupled to a first row of memory cells on the first semiconductor layer, the second memory cell block may include a second word line coupled to a second row of memory cells on the second semiconductor layer, and the first word line may be between the first and second semiconductor layers. The first row decoder may be configured to control the first word line, and the second row decoder may be configured to control the second word line. A first wiring may electrically connect the first row decoder and the first word line, and a second wiring may electrically connect the second row decoder and the second word line.