Trillium vaseyi is a species of flowering plant in the family Melanthiaceae.

[5] Trillium vaseyi was named and described by the American botanist Thomas Grant Harbison in 1901.

simile based on a type specimen collected by the American botanist Henry Allan Gleason in 1904.

[11][12] Although Gleason stated the flower stalk was "declined or cernuous", that of the type specimen is erect.

[17] As of April 2023[update], the global conservation status of Trillium vaseyi is listed as vulnerable and near threatened by NatureServe and IUCN (resp.).