A stacked semiconductor device and a method of forming a serial path of the stacked semiconductor device are provided. The stacked semiconductor device includes a plurality of chips each having a first internal circuit for receiving an input signal, performing a designated operation and outputting an output signal. Each of the chips includes a serial bump disposed at the same position on one surface of each of the chips, receiving the input signal and transferring the input signal to the first internal circuit, and a serial through-silicon via (TSV) disposed at a position symmetrical to the serial bump with respect to a center of the chip to penetrate the chip, and receiving and transferring the output signal. Here, the chips are alternately rotated and stacked, so that the serial TSV and the serial bumps of adjacent chips contact each other. According to the stacked semiconductor device and method, a plurality of chips having the same pattern are rotated about the center of the chips and stacked, so that a parallel path and a serial path can be formed.