Water chestnut or ‘Singhara’ or ‘Paniphal’, is an important annual aquatic vegetable in many parts of India. The plant was severely infested by Singhara beetle, Galerucella birmanica during July to November in Varanasi region. Almost 100% plants and 70 – 80% leaves were infested by the grubs and adults of this beetle. Under laboratory conditions the biology of the pest revealed that, the incubation, larval and pupal periods were 4.15 ± 0.56, 12.75 ± 0.80 and 2.80 ± 0.40 days, respectively. Adult females lived longer (21.10 ± 1.57 days) than the males (16.38 ± 0.77). Gravid females laid on an average 90.4 ± 14.67 eggs, whereas egg viability was 58.9 ± 3.75 per cent. Amongst the different biopesticides tested, neem oil was found most promising having lowest median lethal time of 17.32 h followed by Metarhizium anisopliae IIVR strain (52.67 h). Combinations of these entomopathogenic fungi (EPF) and neem oil (1:1) had lower LT₅₀ values than each of their individual indicating the compatibility among them. The present study will be helpful in developing future integrated management strategies of this nefarious pest in India relevant to aquatic cropping systems.