Carex cusickii is a species of sedge known by the common name Cusick's sedge. It is native to Northwestern North America from British Columbia to California, and in Utah, where it can be found in several types of wet habitat, such as marshes, mountain meadows, and ditches. In its range it is most common in the Cascade Range and areas west.
The Carex cusickii sedge produces clumps of stems up to 1.3 meters tall. It is sometimes dioecious, with male and female flowers occurring on different individuals. The long leaves have sheaths dotted with red and edged at the top with copper. The inflorescence is often separated into distinct bunches of spikelets.