Provided are a semiconductor device and a method for fabricating the same. The semiconductor device comprises a first fin type active pattern formed on a substrate and extending in a first direction and including first to third parts. At least one dimension of the third part measuring less than the corresponding dimension of the first part. A gate electrode extending in a second direction different from the first direction is at least partially formed on the first part of the fin type active pattern. A first source/drain is formed on the third part of the fin type active pattern.