The Hop River is a river that runs through Tolland County, Connecticut. The Hop River's marshy source is just southeast of Bolton Notch, Connecticut. It flows for about 15.0 miles (24.1 km) to its confluence with the Willimantic River.^[1] There is a popular paddling route beginning where the Skungamaug River enters the Hop River just north of the Hendee Road bridge and ending at the Willimantic River. Most of this route consists of quick-water, but a few Class I and Class II whitewater areas exist.

The Hop River State Park Trail crosses the river twice and is parallel to the river for the majority of the river's length.

• List of rivers of Connecticut