Lichens of Sirumalai hills are reported here for the first time. Lichen biota comprised of 95 species. The genus Japewiella is reported for the first time in India and is represented by J. tavaresiana (H. Magn.) Printzen. Furthermore, the following six taxa including one variety are new to India viz. Arthonia atra (Pers.) A. Schneid., Graphis brevicarpa M. Nakan., Kashiw. & K.H. Moon, Micarea erratica (Körb.) Hertel, Rambold & Pietschm., Pertusaria cicatricosa var. deficiens A.W. Archer, Elix & Streimam, Porina subargillacea Müll Arg., and Pyxine schmidtii Vain. Brief accounts for all the new records to India are provided to facilitate their identification. Arthonia redingeri Grube and Lepraria caesiella R.C. Harris are reported for the first time from south India. Besides all above, 29 species are recorded for the first time from the state of Tamil Nadu. The lichen biota of the area is primarily corticolous in habitats and dominated by crustose form. Keywords – lichenized fungi – new records – south India – Tamil Nadu – tropical lichens.