The Sandi Bird Sanctuary is a distinctive wetland system situated in Uttar Pradesh’s Indo-Gangetic region that experiences significant anthropogenic impact. The present study documents the diversity of vascular plants and their threat status. Observations and occurrences of different types of flora, like herbs, shrubs, trees, and climbers, have been completed. The sampling was carried out for pre-monsoon (April to May), monsoon (June to September), and post-monsoon seasons (October to December) in 2023-2024. In each season, the survey was done with an appropriate time interval. After being observed and recognized in the field, the specimens of the various species were subsequently identified in a lab for complete description. The vascular plant diversity in all three seasons (rainy, winter, summer) was recorded as about 157 Species belonging to 119 Genera and 53 families from Sandi Bird Sanctuary. The most dominant family was Poaceae (20 species), followed by Fabaceae (17 species), Cyperaceae (16 species), Asteraceae (12 species), and Amaranthaceae (7 species). The most dominant genus was Cyperus with 8 species. The aquatic areas were largely dominated by two communities, viz., Pontederia and Azolla, whereas the terrestrial areas were by Lantana and Parthenium. For improved management, the sanctuary must strategically eradicate invasive species and plant native species.