Located in southern Iran, the Lut Desert is one of the world's most extreme and unique arid environments. It was inscribed as Iran's first Natural World Heritage Site by UNESCO in 2016. Although often perceived as barren and lifeless due to its harsh conditions, this region exhibits remarkable botanical significance. This study aimed to conduct a comprehensive survey of the floristic composition and life forms in key subregions of the Lut Desert. Extensive fieldwork was carried out across five major sites during the spring and summer of 2021. For all plant species, we documented key traits including life form, cotyledon type, growth form, life span, chorotype, NCBI ID, and IUCN conservation status. Chorological analysis of the 76 recorded plant species (64 genera, 31 families) classified them into monoregional, biregional, and pluriregional groups, with the Irano-Turanian/Saharo-Sindian chorotype being the most dominant (30.3%). Plant distribution is primarily influenced by elevation and geographic location, with the highest species richness observed at mid-high elevations (764-1386 m) and in the northwest quadrant. Key species, such as Hammada sal/corn/ca, demonstrate wide adaptability across these environmental gradients. The flora is dominated by perennial shrubs and grasses (93% of species), mainly phanerophytes and hemicryptophytes, reflecting adaptations to extreme aridity. In a rare pattern, both species richness and phylogenetic diversity increase monotonically with elevation, reaching their highest levels at upper elevations (>750 meters) due to milder temperatures, increased precipitation, and improved soil conditions. The discovery of one threatened species, Haloxylon persicum, underscores the conservation importance of this desert ecosystem. This study reveals a critical elevation-diversity relationship and underscores the ecosystem's vulnerability to climate change and human impacts, necessitating targeted conservation. Contrary to prior views of it being barren, the Lut Desert hosts significant plant diversity, acting as a biological refuge.