Threatened flora of Sierra Nevada (2100 vascular taxa -species and subspecies- catalogued, which means 30% of the entire vascular flora of Iberian Peninsula) has been studied. Habitat, status, corology and threats of 116 taxa were examined. Among threats, they cited infrastructure, construction and gravel quarrying. Threatened flora was catalogued by: a) geographical distribution (W= wide, N= narrow), b) habitat specificity (B= broad, R= restricted), c) local population size (L= somewhere large, S= everywhere small). Threats: 1= natural causes, 2= overgrazing, 3= fire, 4= collecting, 5= deforestation-tree falling-inappropriate forestry practices, 6= introduction of exotic species-foreign genetic material, 7= farming, changes in agricultural practices, 8= wetland, desiccation, water pollution, 9= refuse contamination, 10= recreational activity, 11= infrastructure, construction, gravel quarrying. Palabras clave: Flora, Habitat loss, Plant, Pollution, Vegetation