Genetic variation of Pavo muticus between Doi Phu Nang National Park and Wieng Lor Wildlife Sunctuary populations by 330 bp by mitochondrial D-loop nucleotide sequence. It is found there are 26 variable site, 14 informative sites, 16 transition sites and 8 transversion sites in Doi Phu Nang National Park population. And its genetic distance ranges between 0.0000 and 0.0513. Meanwhile, there are 7 variable sites and transition in Wieng Lor Wildlife sanctuary population, and its genetic distance ranges between 0.0000 and 0.0219. According to the nucleotide sequence study between the two populations, there are 24 variable sites, 16 transition sites and 8 transversion sites and their genetic distance is between 0.0000-0.0547. Genetic diversity of Pavo muticus within Doi Phu Nang National Park and nucleotide diversity within Wieng Lor Wildlife Sunctuary is 1.92 and 0.22 respectively. These result reveal that genetic variation of Green Peafowls from Doi PhuNang National Park is higher than that of Wieng Lor Wildlife Sunctuary. The analysis of phylogenetic relationship using parsimony approach found that one group of population of Doi Phu Nang and Wieng Lor Wildlife Sanctuary are still to related, and another group of Green Peafowls of Doi Phu Nang National Park has been diverged. The consistency index (Cl) is 0.949 and retention index (Rl) is 0.853.
