A new plant species, Cyphostemma annamalaii, has been discovered on Sanjeevi hill in Villupuram district of Tamil Nadu, a part of the southern Eastern Ghats. The plant belongs to the Vitaceae family, the grape family that mostly consists of climbing plants. The discovery adds to the recorded plant wealth of the southern Eastern Ghats in Tamil Nadu and underlines the conservation value of the State’s isolated hill habitats. It is relevant for questions on new species reported from Tamil Nadu.