Resumo. The bronze bug Thaumastocoris peregrinus is native from Australia and has been detected in Brazil since 2008, causing damages in eucalyptus plantations. This insect feeds on phloem-sap, preferentially on the oldest leaves that evolves into chlorotic spots and later in bronze spots. In high infestations, plant defoliation may occur. Although the presence of bronze bug on eucalyptus trees has been often recorded, still there is lack of behavioral studies. Therefore, the biology of the Thaumastocoris peregrinus was evaluated in different species of eucalyptus, commercially available in Rio Grande do Sul state. From all tested species, Eucalyptus dunnii conferred the greatest longevity, number of adults, egg and insect viability.