Flies of family Tabanidae are true Brachyceran flies in the infraorder Tabanomorpha and superfamily Tabanoidea. They are commonly known as "Dansmachi" in India. They are true flies of varying sizes, commonly known as deerfly, horsefly and clegs for their disease causing vector capabilities in different wild animals such as horses, deer, cattle and other livestock. They are mainly large-bodied, sturdy flies and their size ranges from 7-33 mm, known for their furious bite to vertebrate animals including humans. This publication gives a taxonomic account of the horse flies found in West Bengal, India.