The Shetucket River is a tributary of the Thames River, 20.4 miles (32.8 km) long, in eastern Connecticut in the United States.

The Thames River is a short river and tidal estuary in the state of Connecticut. It flows south for 15 miles (24 km) through eastern Connecticut from the junction of the Yantic River and Shetucket River at Norwich, Connecticut, to New London and Groton, Connecticut, which flank its mouth at Long Island Sound. The Thames River watershed includes a number of smaller basins and the 80-mile (130 km) long Quinebaug River, which rises in southern Massachusetts and joins the Shetucket River about four miles northeast of Norwich.