A semiconductor memory device which includes a memory cell including two or more sub memory cells is provided. The sub memory cells each including a word line, a bit line, a first capacitor, a second capacitor, and a transistor. In the semiconductor device, the sub memory cells are stacked in the memory cell; a first gate and a second gate are formed with a semiconductor film provided therebetween in the transistor; the first gate and the second gate are connected to the word line; one of a source and a drain of the transistor is connected to the bit line; the other of the source and the drain of the transistor is connected to the first capacitor and the second capacitor; and the first gate and the second gate of the transistor in each sub memory cell overlap with each other and are connected to each other.