The Sample Study on Avifaunal Diversity of East Sikkim was conducted by Lina Chatterjee in the month of May 2023 and the identification and data analysis was done by Nature Mates-Nature Club team. This dataset covers the areas Rongli, Padamchen and Zuluk which lie under Pangolakha wildlife sanctuary, Thambi and Nathang. The study area covers varied habitats like hilly terrain, village landscape, mountain landscape, high altitude lake, valleys, snow-capped mountain, alpine, sub alpine, temperate forest with rhododendron plants and oak,silver fir, juniper, pine trees and bamboo thickets. All the species are identified up to the species level. A total of 121 species of birds are recorded belonging to 39 families and 9 orders. This dataset also includes the life stage, activity and behavior of the birds observed. During our study Bearded Vulture(Gypaetus barbatus), high altitude species like Plain Mountain Finch(Leucosticte nemoricola) and Crimson-browed Finch(Carpodacus subhimachalus) which are rare were recorded.