Chinook Peak, Mountain summit in Mount Rainier National Park, Washington, US.

Chinook Peak is a 6,904-foot (2,104 m) summit on the eastern border of Mount Rainier National Park, on the shared line between Pierce and Yakima counties in Washington. It stands north of Chinook Pass on the crest of the Cascade Range, 1.31 miles south of Crystal Mountain, with Crystal Peak 0.75 miles to the northwest and Cupalo Rock 1.0 mile east-northeast. Runoff drains into tributaries of the White River and Yakima River.

The peak marks a county boundary that became established when Mount Rainier National Park was created. This geographical division has influenced how the surrounding mountain landscape has been managed and protected.

Chinook Peak sits on the border of Pierce and Yakima counties, and its runoff feeds tributaries of both the White River and the Yakima River. The name Chinook is shared with the nearby Chinook Pass just to the south, the route the peak overlooks on the crest of the Cascades.

The peak is most accessible during warmer months when snow coverage is reduced. Visitors should prepare for steep terrain and exposed conditions that require mountain climbing experience.

The peak receives heavy wet snowfall during winter months due to maritime weather influences. This type of snow creates distinct climbing challenges compared to the drier conditions found on other peaks in the range.