A semiconductor device in which the cell size is small and disturbance in reading operation is suppressed, and a method for manufacturing the semiconductor device. A first memory cell has a first memory transistor. A second memory cell has a second memory transistor. A control gate is shared by the first memory cell and the second memory cell. In plan view, the control gate is sandwiched between a first memory gate of the first memory transistor and a second memory gate of the second memory transistor.