A semiconductor device includes a substrate that includes a first active region and a second active region, a device isolation layer between the first active region and the second active region, a gate structure that extends in a first direction and runs across the first active region and the second active region, a first active contact pattern on the first active region on one side of the gate structure, a second active contact pattern on the second active region on another side of the gate structure, and a connection pattern that is on the device isolation layer and connects the first active contact pattern and the second active contact pattern to each other. The connection pattern extends in a second direction and runs across the gate structure. Portions of the first active contact pattern and the second active contact pattern extend in the first direction and overlap the device isolation layer.