Butterflies are sensitive species having very important role in ecosystem as pollinators and ecological indicators. They are vital for estimating quality and sustainability of the ecosystem. In the present study Butterfly diversity at St Mary’s College, Thrissur, Kerala was investigated for the period from January 2016 to December 2019. The results indicates that the campus has diverse butterfly fauna. 46 species of butterflies belonging to five families were recorded. Nymphalidae was dominant group with 19 species followed by Lycaenidae 7, Papilionidae with 9 species, Hesperidae with 5 and Pieridae with 6 species. On analysing the abundance status, it was found that 9 species were very common, 25 species were common, 7 were rare, 5 Very rare.