Based on the cytogenetic analyses, Áskell Löve established Pseudoroegneria as a genus in 1980, with the formula as St genome. Pseudoroegneria was upgraded from Elytrigia section Pseudoroegneria Nevski that was defined by C.A. Heвскᴎй. After more than half-century analyses, it was proved that Pseudoroegneria served as a key St donor for many alloploidy in Triticeace species, i.e., Anthosachne, Campeiostachys, Douglasdeweya, Elymus, Kengyilia, Roegneria, Trichopyrum. Those species contain St genome mainly distributed in Asia and Europe, North and South America, Oceania, and Africa, serve as an important component of grassland, meadow, even to the forest, desert grass. St genome associate with H genome, Y genome, and Ns genome are four basic genomes in triticeae species. Thus, Pseudoroegneria occupies an important role in the systematics of triticeae species.