The mudskipper Periophthalmus walailakae (Gobiidae) is here first recorded from the Vellar estuary, southeast India. A total of 5 specimens were collected from three stations in April-December 2017. Their total length (TL) ranged from 40 mm to 159 mm and their body weight ranged from 8.3 g to 29.8 g. Diagnostic morphometric and meristic characteristics were measured and compared with museum specimens donated by the Natural History of Museum, Singapore (LKCNHM, ZRC). Despite their abundance in the Vellar estuary, its mudskipper assemblages are poorly studied, and very few reports are available on their diversity. These results greatly extend the known distribution of P. walailakae, previously reported from the Straits of Malacca, along the west coast of the Malay Peninsula.