禾本科布氏白粉菌（学名：Blumeria graminis）是属于白粉菌目白粉菌科布氏白粉菌属的一种真菌，寄生在禾本科植物上。该种分布于全世界。

Blumeria graminis (commonly called barley powdery mildew or corn mildew) is a fungus that causes powdery mildew on grasses, including cereals. It is the only species in the genus Blumeria. It has also been called Erysiphe graminis and (by its anamorph) Oidium monilioides or Oidium tritici.