To evaluate the current status of fish biodiversity, a study was carried out in the Pailati beel. It was carried out using key informant interviews (KII), focus group discussions (FGD), questionnaire interviews (QI) of fishermen, and secondary data collection. This water body comprised a total of 55 species, 23 families, and 10 orders, with 20% of the species being abundantly available, 40% of the species being commonly available, 29.09% of the species being moderately available, and 10.90% of the species being rarely available. Barbs and minnows (20%) were discovered to be the most common species, followed by carps (16.36%), catfishes (14.36%), and perches (14.55%). The most dominant order was the cypriniformes (38.18%), followed by the perciformes (20%) and the siluriformes (16.36%). Synbranchiformes, Clupeiformes, Osteoglossiformes, Beloniformes, Decapoda, and Anabantiformes made up the remaining seven classes. The values of the indices for Simpson dominance (C), Pielou's evenness (J'), Shannon-Weaver diversity (H), and Margalef's richness (d) in December, January, and February, respectively, were 0.91, 0.443, 3.25, 5.81, 0.94, 0.451, 3.29, and 5.95. Therefore, the results could be used to design and put into action plans that help to maintain the wetlands in a sustainable way.