The oriental tobacco budworm Helicoverpa assulta (Guenée, 1852) is currently distributed in East Asia, Southeast Asia, Oceania and Africa. However, the origin of this pest remains unknown. In this paper, we review evolutionary relationships among the Heliothinae with emphasis on the phylogeny of H. assulta. Based on its feeding habits, behavior, distribution patterns and host plant range, we infer that H. assulta most likely originated from tropical rain forest regions. We justify this inference with factors associated with the population characteristics of H. assulta, including human activities and plate tectonics.