We draw the attention to the existence of two transmitter species of Chagá's desease in the State of Maranhão, Brazil, the Panstrongylus megistus (BURMEISTER, 1835) PINTO, 1931 and the Triatoma rubrofasciata (DE GEER, 1773) KIRKALDY, 1907 besides the Panstrongylus geniculatus (LATREILLE, 1811) PINTO, 1931, whose presence was already known in that State.