The purpose of this study was to investigate the sugar-feeding behavior of Anopheles quadrimaculatus by measuring the impact of different aquatic plants on its survival. At the same time, the potential use of boric acid in toxic sugar bait (TSB) applications to the leaves of these plants was also evaluated. Mean survival rates of mosquitoes after 120 h feeding on 3 common aquatic plant species-Thalia geniculata, Pontederia cordata, and Limnobium spongia-were 10.55%, 1.86%, and 6.21%, respectively. No significant difference in mortality between mosquitoes feeding on separate plant species was detected (P = 0.05). The TSB efficacy was evaluated by leaf dip bioassay to compare 24-h mortality of mosquitoes feeding on leaves treated with TSB formulation (1% boric acid, 10% sucrose) and leaves dipped in 10% sucrose. Mortality was significantly higher for TSB-treated leaves for T. geniculata (t = 12.5, df = 8, P < 0.0001) and P. cordata (t = 5.42, df = 8, P = 0.0006) than for L. spongia (t = 1.4003, df = 8, P = 0.199). One-way ANOVA analysis showed no significant difference in efficacy between TSB-treated leaves of the 3 plants.