樱井草（学名：Petrosavia sakuraii）为樱井草科樱井草属下的一个种。

Petrosavia sakuraii, one of three species in the genus Petrosavia, is a monocotyledonous plant first described by Tomitaro Makino in 1903 (see illustration), distributed in eastern and south-eastern Asia. They are rare leafless achlorophyllous, mycoheterotrophic plants found in dark montane rainforests.