Cryptantha roosiorum is a species of flowering plant in the borage family known by the common name bristlecone cryptantha. It is endemic to Inyo County, California, where it is known from only a few occurrences in the northern Inyo Mountains. It is a small, mat-forming perennial herb just a few centimeters high which grows from a woody caudex rooted in rocky soils. The leaves are up to about a centimeter long, oval to spoon-shaped, and hairy to bristly. The inflorescence is a dense cluster of tiny white flowers with five-lobed white corollas with yellow appendages.