The Huron River is located in the north central area of the U.S. state of Ohio. The watershed drains large portions of Erie County and Huron County, the northeast corner of both Seneca County and Crawford County and the north portion of Richland County.

The mouth is on Lake Erie at the city of Huron. The main branch of the river is formed when the east and west branches merge near Milan.

The east branch arises west of Fitchville and flows west to North Fairfield, where it bends north and flows though Peru and Norwalk before reaching Milan.

The west branch arises about 4 miles south of Greenwich and four miles east of Shiloh, in northern Richland County, within a few miles of the headwaters of both the southwest branch of the Vermilion River (which also flows north to Lake Erie) and the Shipp Creek which ultimately flows south to the Muskingum River and then to the Ohio River. The west branch of the Huron flows north and west to Plymouth where it bends north to flow through New Haven. It passes to the east of Willard, although other tributaries arise north of Willard. The west branch continues north to Monroeville before reaching Milan.

Major tributaries include:

• Mud Brook
• Seymour Creek
• Megglinson Creek
• Frink Run
• Slate Run
• Mud Run
• Cole Creek

The Willard Marsh within the Willard Marsh State Wildlife Area, feeds into both the west branch of the Huron and the Honey Creek tributary of the Sandusky River.