The Sophie River rises below Sophie Peak, part of the West Coast Range within the Granite Tor Conservation Area.

The river flows generally west by north and reaches its confluence with the Mackintosh River within Lake Mackintosh.

The river descends 187 metres (614 ft) over its 20-kilometre (12 mi) course.

[1] Lake Mackintosh and several adjoining reservoirs form part of the Pieman River Power Development scheme and some of the flow of the Sophie River supplies the Mackintosh Power Station for the generation of hydroelectricity.

[2] The Sophia Adit, a small tunnel for maintaining the Sophia Tunnel, is located adjacent to the river.