Abstract <p>Butterflies are a widespread species and play a crucial role in pollination and seed dispersal. This study examines the interaction between butterfly communities and their host and nectar plants, as well as the environmental factors influencing butterfly species richness on the Bangalore University Campus (BUC) in Bengaluru, India. Regular sampling was conducted using the standard line transect method to observe butterflies and document their host and nectar plants. A total of 105 butterfly species, 86 larval host plant species, and 25 adult nectar plant species were identified. Among them, one near-threatened species, <i>Parantica nilgiriensis</i>, was recorded, while the rest were classified as least concern. <i>Catopsilia pomona</i> and <i>C. pyranthe</i> were observed year-round, with <i>Acraea terpsicore</i> being the most abundant species. Nymphalidae was the most dominant butterfly family. Among host plants, <i>Cassia tora</i> had the highest density on campus, while Fabaceae was the most abundant and diverse larval host plant family. <i>Cadaba fruticosa</i> attracted five Pierid butterfly species, while <i>Ixora coccinea</i> and <i>Lantana camara</i> were popular nectar sources. Relative humidity showed a positive correlation with the abundance and richness of Nymphalidae butterflies. This study highlights the rich diversity of butterfly species and their host plants at BUC, offering valuable insights for conservation and habitat management.</p> Graphical Abstract <p></p>