Galbreath Wildlands Preserve, Protected natural area in Mendocino County, California.

Galbreath Wildlands Preserve is a 3,670-acre former sheep ranch in the Outer Coast Range of southern Mendocino County, about 17 miles inland from the Pacific. Its 900 to 2,200 feet of elevation carries second-growth Douglas-fir and redwood forest, mixed hardwood-conifer stands of tanoak and madrone, black and Oregon white oak woodlands, and annual grassland. Rancheria Creek flows north through the preserve into the Navarro River.

The land was a sheep ranch when Fred Burckhalter Galbreath (1901–2000) bought it in 1944; he cut sedimentation through drainage work, hunted invasive wild boar and thinned old and diseased trees. He died at 98, and his family (Bob and Sue Johnson, Nancy and Kleve Johnson) donated the property to Sonoma State University through a living trust in 2004, when the preserve was established in his honor.

Central Pomo villages stood near the preserve along Rancheria Creek: Late, about a mile west of Yorkville, whose people coastal Pomo called Danokeya, or "upstreamers," plus Polma, Kalaicolem and Lali. Each tribelet of 100 to 2,000 people was led by a headman from each extended family, who sat on a tribal council.

The preserve is reached via Yorkville, about 5 miles (8 km) away; Cloverdale lies 20 miles (32 km) off and Boonville 18 miles (29 km). Rancheria Creek flows north through the property and drains into the Navarro River. Terrain ranges from 900 to 2,200 feet (270 to 670 m), and lands are managed for research and education rather than public recreation.

The preserve's streams are classified as 1st- to 5th-order waterways of the upper Rancheria sub-basin, draining north into the Navarro River. The land sits at the edge of the coastal fog belt, and its forests are mainly second-growth conifer and hardwood, regrown after heavy Douglas fir and redwood logging between the late 1800s and early 1900s.