A manufacturing method of a semiconductor device includes the following steps. An opening is formed penetrating a dielectric layer on a semiconductor substrate. A stacked structure is formed on the dielectric layer. The stacked structure includes a first semiconductor layer partly formed in the opening and partly formed on the dielectric layer, a sacrificial layer formed on the first semiconductor layer, and a second semiconductor layer formed on the sacrificial layer. A patterning process is performed for forming a fin-shaped structure including the first semiconductor layer, the sacrificial layer, and the second semiconductor layer. An etching process is performed to remove the sacrificial layer in the fin-shaped structure. The first semiconductor layer in the fin-shaped structure is etched to become a first semiconductor wire by the etching process. The second semiconductor layer in the fin-shaped structure is etched to become a second semiconductor wire by the etching process.