Symmes Creek is a 76.4-mile-long (123.0 km) tributary of the Ohio River in southern Ohio in the United States. Via the Ohio River, it is part of the watershed of the Mississippi River, draining an area of 357 square miles (920 km2) on the unglaciated portion of the Allegheny Plateau. The United States Board on Geographic Names settled on "Symmes Creek" as the stream's name in 1902. According to the Geographic Names Information System, it has also been known historically as "Simms," "Big Creek," and "Symms Creek."