A laboratory study was conducted to understand the effect of low concentrations of lufenuron on termite physiology and behavior. Survivorship, running speed, body water content, food consumption, tunneling, microbial infection, and two behavioral patterns (carcass-burying behavior and particle transport behavior) were compared among Formosan subterranean termites, Coptotermes formosanus Shiraki, fed lufenuron-treated (250, 500, or 1,000 ppm) or untreated (control) filter paper. In 30-32 d, all lufenuron treatments significantly reduced survivorship, running speed, consumption, and tunneling, but had no substantial effect on body water content. In addition, termites fed the three concentrations of lufenuron became infected by opportunistic pathogens. Carcass-burying and particle transport behaviors also were inhibited by lufenuron. Potential application of lufenuron at low concentrations for the control of C. formosanus is discussed.