A semiconductor device and method of forming the same, the semiconductor device includes a first and second fin shaped structures, a first and second gate structures and a first and second plugs. The first and second fin shaped structures are disposed on a first region and a second region of a substrate and the first and second gate structure are disposed across the first and second fin shaped structures, respectively. A dielectric layer is disposed on the substrate, covering the first and second gate structure. The first and second plugs are disposed in the dielectric layer, wherein the first plug is electrically connected first source/drain regions adjacent to the first gate structure and contacts sidewalls of the first gate structure, and the second plug is electrically connected to second source/drain regions adjacent to the second gate structure and not contacting sidewalls of the second gate structure.