The headwaters are on the Mount Hood's south face at the foot of Palmer Glacier east of Silcox Hut.

The river, which crosses the Pacific Crest Trail at 5,980 feet (1,820 m), continues directly southward for a few miles and remains east of Timberline Road.

[6] The West Fork Salmon River begins in the Timberline Lodge ski area under the Pucci chairlift.

[6] A steep east–west gorge captures the Salmon River and collects several creeks—Wolf from the right; Inch, Draw String, and Linney from the left.

[6] The river turns northwest and in the next 3 miles (5 km), flows over a series of six waterfalls ranging from 15 to 75 feet (4.6 to 22.9 m) high.

From here the river flows 11 miles (18 km) on a comparatively level grade, receiving Cheeney Creek from the left just above Welches.

Receiving Boulder Creek from the left, it crosses (again) under Route 26 and merges with the Sandy River near the community of Brightwood.

[1] Whitewater enthusiasts sometimes run a stretch of the lower river that begins downstream of the Salmon–Huckleberry Wilderness boundary.

Huge, marginally portageable waterfalls combined with crumbly, near-vertical canyon walls and questionable rescue possibilities make this a very serious venture indeed.

The highest campground in the Mount Hood National Forest, it is near Timberline Lodge and offers access to trails for hiking and mountain biking.

[15] This trail, 14 miles (23 km) long, generally runs along a forested bluff above the north side of the river.