Argonaut Peak is a tall mountain in the Cascade Range in the U.S. state of Washington.

Its southern side slopes down to the valley of Ingalls Creek.

[3] Argonaut Peak is 1.7 miles (2.7 km) west of Isolation Lake and 1.8 miles (2.9 km) east of Mount Stuart.

[2] Argonaut Peak is a large bastion of clean granite rock,[4] part of the Mount Stuart batholith.

Argonaut Peak was first summited, via the south route, in September 1955 by Lex Maxwell, Bob McCall, and Bill Prater.