Ionian Zone in western Greece is a possible hydrocarbon producing area. Oil seeps are abundant in the area and the zone is a continuation of the Albanide tectonic zones with active oil fields. The Ionian Zone is composed of Triassic evaporites and carbonates that are overlain by Jurassic-Cretaceous carbonates and Cretaceous-Tertiary clastics. The units under the evaporites are believed to host the most attractive plays in the area. However, these units have never been reached. This article summarizes the lithological description of units that come from areas around the Ionian Zone and some geophysical evidence in an attempt to unravel this unknown lithology. Tectonic movements in Miocene to Pliocene times have a serious effect on this lithology and the role of the evaporites in the tectonics is highly underlined. Maturity modeling shows that the units under the evaporites produce hydrocarbons and hence comprehensive studies aiming to target these plays are more than essential.