Avian diversity of Tilyar Lake (28.883–28.879 0N & 76.637 –76.634 0E)  located on the eastern outskirts of Rohtak, Haryana was conducted from May 2017 to April 2018.  A total of 73 avian species belonging to 62 genera and 31 families under 15 orders was observed. Order Passeriformes with 21 species in 12 families dominated the avifauna whereas orders Bucerotiformes, Podicipediformes, and Psittaciformes were poorly represented with a single species each.  Family Anatidae was the most dominant representing 13.89% (n=10) of the total species recorded.  Among the reported species 75% (n=54) were resident while 25% (n=18) were migrant.  Common Pochard Aythya ferina assessed globally as Vulnerable, while Painted Stork Mycteria leucocephala, Oriental Darter Anhinga melanogaster and Black-headed Ibis Threskiornis melanocephalus are assessed as Near Threatened, whereas the rest of the species were in the Least Concern category of the IUCN Red List 2019.  The omnivorous feeding habit was shown by the maximum number of species while frugivorous and granivorous bird species were in the least numbers.  The rich avifaunal diversity of the Tilyar Lake confirms it as a suitable habitat for both resident and migrant bird species. Therefore, the present study suggests the need for incorporation of appropriate protective measures for conservation of the avian heritage of Tilyar Lake, Rohtak.