A semiconductor device includes an active pattern including a channel region. The channel region is disposed between first and second source/drain patterns that are spaced apart from each other in a first direction. The channel region is configured to connect the first and second source/drain patterns to each other. A gate electrode is disposed on a bottom surface of the active pattern and is disposed between the first and second source/drain patterns. An upper interconnection line is disposed on a top surface of the active pattern opposite to the bottom surface of the active pattern and is connected to the first source/drain pattern.