The abundant medicinal plant resources are the material basis for the vigorous development of traditional Chinese medicine (TCM) and an important guarantee for people's life and health in China.However,due to the increasing demand and the deterioration of the natural environment,some important medicinal plant species are becoming increasingly scarce,and some are even in an extremely endangered situation.These rare and endangered medicinal plant species often have unique curative effect and are an important component of TCM resources,so corresponding measures should be taken to preserve and restore them.In vitro conservation is a new method of plant resources preservation based on plant tissue culture technology,which has many advantages.It has become the main way to promote the conservation,recovery and sustainable utilization of rare and endangered medicinal plant resources,and plays an important role in the development of TCM.In view of this,the main types of rare and endangered medicinal plant resources were systematicly combed according to the endangered degree of resources.The latest research progress on tissue culture conservation,ultra-low temperature conservation and gene resource conservation which included in in-vitro preservation technology was elaborated from these aspects such as the basic principle,operation process,key technical links and application examples.Meanwhile,the problems existing in the in vitro conservation of rare and endangered medicinal plant resources were summarized and analyzed.In addition,the future research directions in this field were prospected.This review will provide some references for the protection,expansion and development of rare and endangered medicinal plants.