Salep is a powder produced from dried tubers of terrestrial orchids which is used to prepare traditional ice creams and beverages. There are 46 Iranian terrestrial orchid species in Iran which 36 species produce underground fleshy tubers. In this regard, west of Iran is a hotspot for most endangered and threatened species. Recently researches have been conducted to study different biological, molecular and conservational aspect of Iranian Terrestrial orchids. In this paper, we aimed to review current research progress on Iranian terrestrial orchid species. Metabarcoding has been successfully used to understand the species diversity and provenance of salep orchid tubers. Morphological traits at whole plant scale combined with seed-micromorphology characters could discriminate and clarify the relationships among the Iranian species and their geographically different populations. The inter- and intra-population variation of most endangered Iranian orchid species were successfully discriminated using of ISSR, IRAP and SCoT molecular markers. Ongoing phytochemical studies represent the presence of high value constituents in hydroalcoholic extract of leaf and tubers. On the other hand, efforts to conserve threatened species led to optimization of asymbiotic seed germination and in vitro multiplication of seven most important Iranian orchid species. More comprehensive and applied researches are needed to study different biological and ecological aspect of Iranian orchid species to define conservational strategies.