The authors have surveyed different habitats in and around the Unakoti Archaeological Site and documented a total of 216 species classified under 6 families, 23 subfamilies and 126 genera of the order Lepidoptera. The study was conducted from 2016 to 2020, covering different seasons namely pre-monsoon (Jan-Apr), monsoon (May-Aug) and post-monsoon (Sep-Dec) respectively. The study reports 2 species under schedule I, 25 species under schedule II, and 5 species under schedule IV of the Indian Wildlife (Protection) Act 1972. This study also documented seasonal diversity and habitat-wise occurrence of butterflies in and around the Unakoti Archaeological Site. During the study, 59 butterfly species were recorded as new additions to the butterfly fauna of Tripura. High-quality photographs of all the butterfly species documented during the study have been included in this paper.