Kolleru Lake is the largest freshwater lake in India, located between West Godavari and Krishna districts of Andhra Pradesh. Being the largest freshwater body, Kolleru Lake supports rich aquatic medicinal flora and as an elevated land between Godavari and Krishna rivers, it provides good habitat for many terrestrial medicinal plants. At the time of the floristic survey, this study identified 11 aquatic and 24 terrestrial flora in Kolleru. In and around Kolleru area 35 medicinal plants were reported from 17 sites, out of 35 medicinal flora, 11 aquatic flora and 24 terrestrial plants were identified. Aquatic medicinal flora including Ipomea aquatica, Nymphaea nouchali, Nelumbium species, Salvinia cumulata Alternanthera sessilis, Typha angustata, Cypress rotundus, Ecilipta alba, Scripus articilum, Cynodon dactylon, Utricularia species was identified in Kolletikota, Gudivakalanka, Atapaka, Pedayadlagadi bridge. Terrestrial plants like Aerva lanata, Andrographis paniculata, Asystica gangetica, Abrus precatorius, Achyranthes aspera, Cassia occidentalis, Euphorbia hirta, Gloriosa superba, Hemedesmis indica, Tridax procumbence, Oscimum sanctum, Ricinus communis, Vitex negundo, Rauwolfia serpentina, Bixa octandra, Sida acuta, Abutilon indium, Acalypha indica, Tephrosia purpurea, Centella asiatica, Coccinia indica, Boerhavia diffusa, Crotan banplandianum, Phyllanthus madraspatens were identified in belt villages of the lake. During the last two decades, water quality and other environmental changes in Kolleru Lake resulted in stress on the biodiversity of the ecosystem. If these medicinal plant species properly maintained, harvested and marketed then it can be another source of livelihood of Kolleru area.