: Analysing patterns and mechanisms that affect speciation is the cornerstone of evolutionary biology and biogeography. Apart from mutation-order speciation that happens stochastically during evolutionary time-scales, ecological divergence and adaptation to local conditions is a measurable model of speciation that allows evaluating historical divergence and biogeography. Indeed, species divergence through ecological gradients leads to genetic differentiation and separation in phylogenetic trees. Ecological niche modeling enables quantifying ecological niche, comparing species tolerance in ecological gradients and mapping their geographic distribution. Mountain vipers of the genus Montivipera represent interesting cases of ecological speciation in high-plateaus of Iran, Anatoly and Caucasus. In one hand their global distribution is limited to this area, and in another hand, high rates of speciation in term of neo-endemism has been happening in this genus. Given the necessity of proper recognition of the taxonomic status of the Montivipera genus as well as the high-priority to plan conservation implications, this study was implemented aiming at evaluating phylogenetic divergence and ecological speciation of the genus. For this purpose, using all the genetic sequence of the GeneBank and sequences amplified from the tissues gather during direct filed sampling, phylogenetic tree of the genus was reconstructed. In addition, network of haplotypes and divergence time of the identified lineages was illustrated. In the next step, using occurrence points and environmental variables ecological niche of the species was explored. Combining the information obtained from these two steps allowed to identify cryptic species and evaluate ecological niche evolution of the species. Moreover, given the critical role of climate on the geographic range of mountain vipers, impacts of climate change on the distribution of these species was assessed. The current PhD dissertation is organized in three main chapters: exploring genetic differentiation and phylogenetic relationships, assessing ecological niche divergence and evolution, and evaluating impacts of climate change on the geographic range and extinction risk of mountain vipers. In the end, results of each chapter in terms of phylogeny and ecological niche of the species have been discussed. Results of this PhD dissertation conclude that due to the low genetic diversity, low rates of ecological niche adaptability and high sensitivity to environmental change, implementing priority-setting conservation implementation is urgent for this unique genus of vipers in Irano-Anatoly bioregion. Keywords: Speciation, ecological tolerance, phylogeny, ecological niche modeling, climate change, mountain vipers.