Acacia crassicarpa (Fabales, Fabaceae) is a tree native to Queensland in Australia, Papua New Guinea and West Papua in Indonesia. Spodoptera exigua and Spodoptera litura (Lepidoptera, Noctuidae) are native to Asia; however, they are currently distributed to several continents where they feed on plants as generalist defoliating pests. The objective of this study was to report, for the first time, Spodoptera species on A. crassicarpa plants in Sumatra, Indonesia. Aim also included the identification of Spodoptera species through analysis on the external morphology of caterpillars and wing venation of adults with confirmation of the identity via molecular analysis. Examination on the external morphology of caterpillars and wing venation of adults, revealed presence of two species i.e. S. exigua and S. litura, which was confirmed through molecular analysis. This is the first report of S. exigua and S. litura on A. crassicarpa. The identification of S. exigua and S. litura is important information for the management of these pests on A. crassicarpa plants in Sumatra, Indonesia.