The olive leaf moth Palpita unionalis (Hubner) (Lepidoptera: Pyralidae) is an international lepidopteran pest originating in the Mediterranean Basin. The present article was prepared aiming to review several aspects of the distribution, economic importance, morphology, biology, ecology and physiology of this pest. Beside the worldwide distribution, economic losses and morphologic characterization, efforts of insect biologists in several parts of the world had been comprehensively highlighted including developmental biology and reproductive biology. From the ecological point of view, population dynamics, sexual and non-sexual behavioral patterns had been discussed. Also, special attention was paid to the laboratory rearing trials on artificial diets. It may be the first review focusing on these aspects of P. unionalis in the world. On the other hand, this pest still needs considerable research work for investigating several aspects such as energy metabolism, homeostasis, enzymatic patterns, hematology, resistance, immunity, reproductive physiology, environmental physiology and the hormonal regulation of these processes. Therefore, the present review enhances the research interests for these important aspects. However, information reviewed herein will support the development of strategies for management of this pest