Laboratory experiments were conducted to evaluate the effectiveness of chlorfluazuron an insect growth-inhibitor against Lutzomyia longipalpis (Lutz & Neiva). Second- and third-instar L. longipalpis were exposed to four different doses (0.65, 0.75, 0.80, and 0.85 mg/ml) of chlorfluazuron added in the larval diet. A direct relationship between dose and larval mortality was observed. Larval mortality was higher in younger larvae. In addition to larval mortality, reduced capacity of the adult females to blood feed, prevention of egg hatching, and morphological abnormalities in adults were noted. A control strategy using chlorfluazuron with other insecticides is suggested to diminish sand fly populations in coffee and cacao plantations.