Altogether eight species of epiphyllous green algae, Trentepohlia were discovered from the rural and semi-urban areas of Southwestern Ghats by field observations and in-vitro culture investigations. The species found were T. abietina (Flotow & Kutzing) Hansgirg, T. rigidula (J. Muller) Hariot, T. annulata, F. Brand, T. aurea (L.) Martius, T. chapmanii Rindi & Lopez- Bautista, T. dialepta (Nylander) Hariot, T. arborum (C. Agardh) Hariot, and T. gaviensis Binoy T.T., Bhagya M.V. & V.P. Thomas sp.nov. They were isolated and observed from the leaves of fourteen host plants. All the species were seen in the areas exposed to full sunlight. Trentepohlia rigidula and Trentepohlia abietina were also observed from the in vitro culture in Bolds Basal Medium (BBM). Three of the species, T. abietina, T. rigidula, and T. chapmanii and were the new records from Kerala; whereas T. dialepta, T. annulata, T. aurea, and T. arborum have been reported in earlier studies. A new species of Trentepohlia is compared with its closely related T. sundarbanensis (G.G. Satpati & R. Pal), T. arborum (C.Ag.) Hariot and T. abietina (Flotow & Kutzing) Hansgirg and is also described in the present study. So far, the diversity of Trentepohlia in tropical regions, particularly in rural and semiurban areas of Kerala was quite unknown. The present investigation indicated that the Southwestern Ghats region of Kerala represents a major habitat zone of epiphyllous algae, particularly Trentepohlia which demands further extensive investigations in the area to explore the complete report of the entire diversity of algae.