Avifaunal diversity survey was carried out from March, 2013 to February, 2016 at Udayasamudram Reservoir, Nalgonda District, Telangana State, India. Transect count and point count methods were used to investigate the abundance of birds. Observations were recorded by periodically walking along 1 square kilometer transects in the morning hours from 06 30 – 09 30 hrs and evening 1600 –1800 hrs. A total of 116 bird species belonging to 17 orders and 48 families and 92 genera were recorded, of which 88 species were resident and 27 were migrant. Among the recorded species, Mycteria leucocephala, Threskiornis melanocephalus, Anhinga melanogaster, Sterna aurantia and Buceros bicornis were near Threatened status, whereas Ciconia episcopus and Sterna acuticauda were Vulnerable and Endangered, respectively. This survey reveals that this reservoir is a suitable habitat for waterbirds. Local villagers lack of knowledge made them participate in poaching. It calls for an urgent need to draft measures and strategies to be taken for proper maintenance and conservation of this water body. Active steps are also needed towards spreading awareness among the locals.