A semiconductor device includes a first chip, a second chip, a third chip, and a fourth chip. The first chip is placed adjacent to the second chip and the fourth chip. The third chip is placed adjacent to the second chip and the fourth chip at a position different from a position of the first chip. Data of the first chip is transferred from the first chip to the third chip via the second chip. Data of the third chip is transferred from the third chip to the first chip via the fourth chip. The data transferred from the first chip to the second chip is transferred via a wiring layer formed over a silicon and placed at a position different from positions of the first chip, the second chip, the third chip, and the fourth chip.