The Mill River is a 17.8-mile-long (28.6 km)^[1] tributary of Otter Creek in Rutland County, Vermont, in the United States.

Mill River
The Mill River in Clarendon Gorge during spring runoff
Location
Country	United States
State	Vermont
County	Rutland
Towns	Mount Holly, East Wallingford, Shrewsbury, Clarendon
Physical characteristics
Source
• location	Mount Holly, Vermont
• coordinates	43°24′15″N 72°48′04″W / 43.40430°N 72.80107°W / 43.40430; -72.80107
• elevation	650 m (2,130 ft)
Mouth	Otter Creek
• location	Clarendon, Vermont
• coordinates	43°30′23″N 72°58′33″W / 43.50629°N 72.97574°W / 43.50629; -72.97574
• elevation	540 ft (160 m)
Length	28.7 km (17.8 mi)

The Mill River rises in the southern part of the town of Mount Holly, west of the Okemo Mountain ski area in the Green Mountains. It flows northwest, paralleled by Vermont Route 155, to the village of East Wallingford, where it continues north and northwest paralleled by Vermont Route 103 and the Green Mountain Railroad. Just before entering the town of Clarendon it passes through Clarendon Gorge, where it is crossed by the Appalachian Trail. It turns west and then southwest at the village of East Clarendon, passes under U.S. Route 7, and reaches Otter Creek 1 mile (2 km) southwest of the village of Clarendon.