The Sand Prairie-Scrub Oak Nature Preserve, formerly called the Mason County State Wildlife Refuge and Recreation Area, is a 1,460 acre (591 ha) State Natural Area and Illinois Nature Preserve located in western Mason County, Illinois.

The preserve does not have on-site staff, and is managed as a disjunct area of Sand Ridge State Forest, a larger conservation area within the same county.

[1] Sand Prairie-Scrub Oak was purchased in 1969[2] and dedicated as a Illinois Nature Preserve in April 1970.

[1] In a 2015 research and inspection fan-out, arborists discovered the first example of dwarf chinkapin oak identified in Illinois.

Prairie grasses such as little bluestem, and sand plant life such as eastern prickly pear cactus, can be found.