<p>This study quantifies community diversity, species richness, and species composition of butterflies and their habitat preferences in a 2.96 sq. km patch of fragmented forest surrounded by human settlements in Tripura bordering Bangladesh. A 12-month field study recorded 661 butterfly individuals representing 87 species belonging to 53 genera and 5 families. The family Nymphalidae representing 38 species and comprising 47.50% of the butterfly individuals dominated the observed diversity. These and individuals of other families collected in the study showed 86.37% sampling completeness according to the abundance-based estimator Chao 1. The edge zone of the forest consisted of human-introduced trees, shrubs, garden flora, and invasive plants, attracting 69 butterfly species. In comparison, the interior zone, containing native trees, shrubs, and invasive plants, attracted 52 butterfly species only. Nineteen of these species (20.69% of 87 species recorded) were exclusively present in the interior zone dominated by the remnant of natural wildlife of un-fragmented forest compared to 37 species (42.53% of the total species recorded) feeding on cultivated, seasonal and invasive plants occurred in the interior as well as edge zones of the forest patch. A strong edge effect was evident in the composition and diversity of butterflies in the fragmented forest patch. Appreciable levels of conservation measures initiated recently have raised the prospect of saving the loss of native butterflies.</p>