The diversity of butterflies (Lepidoptera) with their related host and nectar plants were recorded from the Egra block in Purba Medinipur district of West Bengal. The duration of the work was from June 2019 to August 2019 (3 months) and from March 2020 to November 2020 (9 months) during the lock down period. A total number 80 species of butterflies were found from this block which belongs to 59 genera from five families. Among these, the highest number of species i.e., 26 (32.91%) was recorded from Lycaenidae family in which 11 are legally protected Under the Wildlife (Protection) Act of 1972. From the analysis we found that, the Shannon-Wiener index was 3.272, Shannon Evenness (J’) value was 0.751 and the Simpson's index has a value 0.944. During the study, a total number of 54 host plants from 27 families and 77 nectar plants of 29 families were recorded. However, the major threat here is the application of harmful pesticides and herbicides beyond safe limit associated with agriculture, which not only affected the butterfly diversity, but also destroying overall ecosystem of this rural areas.