Olsynium is a genus of summer-dormant rhizomatous perennial flowering plants in the iris family Iridaceae, native to sunny hillsides in South America and western North America.

Leaves are linear, 4–30 centimetres (1.6–11.8 in) long and 1–3 millimetres (0.04–0.12 in) broad.

Flowers are bell-shaped, with six white, pink, or lilac tepals, and bloom from late winter to spring.

The genus name is derived from the Greek words ol, meaning "a little", and syn-, meaning "joined",[4] referring to the stamens.

[5] The taxon Olsynium was formerly considered as part of the genus Sisyrinchium.