Present study was done with the aim of environmental factors influence on Prangos pabularia Lindl. in Nir and Kousar rangelands of Ardabil province. From seven sites of studied species in two sites present species was observed. In site level, sampling plots was determined and 3 transects with 100m length established and the species density along with each transect 10 plots with 4m² area was recorded. Soil samples from first, mid and final sections of each transect recorded in 0-30cm depth. Adjacent of each site in places without studied species, sampling was done with similar method.

In sampling areas, height from sea level, slope, aspect, and soil characteristics was detected. Independent t test and cluster analysis was applied for comparison and classification of studied species in places with and without species, discriminant analysis was used for effective parameters. Regarding to results in places with high elevation and slope and in places with southern and western aspects and high soil organic matter and high sand and nitrogen, phosphorus and potassium and low clay, the density of studied species was more. The results of discriminant analysis indicated that EC, pH, OC, N, P, Elevation, Slope, Aspect, Percent Clay and Sand and Precipitation are effective in detection of places and dispersion. Regarding to results, it is can be concluded that present species is suitable for better management, restoration of rangelands.