新麦草（学名：Psathyrostachys juncea）是一种禾本科植物。这种植物产于中国**天山以北；此外，蒙古、美国、加拿大、苏联均有分布。

Psathyrostachys juncea is a species of grass known by the common name Russian wildrye. It was formerly classified as Elymus junceus. It is native to Russia and China, and has been introduced to other parts of the world, such as Canada and the United States. Psathyrostachys juncea is a great source of food for grazing animals, as it has high nutrition value in its dense basal leaves, even in the late summer and autumn seasons. This species can grow and prosper in many harsh environments, making it an ideal candidate for improvement as it can grow in areas were farming is difficult. This species is a drought-resistant forage plant and can survive during the cool seasons. It is also a cross-pollinator and is self-sterile. This means that P. juncea cannot self-fertilize; it must find another plant of the same species with which to exchange gametes. Self-sterilization increases the genetic diversity of a species.