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Bintuni Basin is a Tertiary basin located in the Bird’s Head area of Papua. This basin became a foreland basin after the Lengguru Fold-Thrust Belt (LFTB) formed through the collision between Australia, Eurasia and Pacific plates causing a complex tectonic history. The LFTB formation appears to affect source rock maturation distribution in the foredeep area of Bintuni Basin. In Bintuni Basin the Ainim formation, part of the Aifam group, is unconformably deposited over the Aifat formation. This Permian formation consists of shale, claystone, siltstone, coal, sandstone and coaly shale. The main source rock lithologies in this interval are coal, claystone and shale. This information has been obtained from 9 wells both offshore and onshore. Geochemical characterization was performed to determine type of organic material, maturity, and organic richness of Permian source rock area and produce Vitrinite Reflectance (Ro), TOC, and Hydrogen Index (HI) maps as a result. The objective of this study is to determine Permian maturation distribution related to LFTB position in this foreland basin. The organic material distribution increases from northeast to southeast with average TOC between 0.264 – 40.69 %, HI between 32 – 198.5 mg HC/g TOC, and with some coal occurrences. The type of organic material is type III gas-prone kerogen. Terrestrial organic material distribution is most likely related to basin paleogeography, which in the Permian tend to be more landward toward the southeast. The maturity of Permian source rock increases to the northeast of Bintuni Basin towards the LFTB position and reaches 1.5 % Ro onshore Bintuni Bay. The maturity increase coincides with LFTB overburden position in the northeast, which buried the Permian source rock in the foredeep system in front of the thrust belt and also shows that natural gas in Bintuni area is more likely to come from the northeast area. Keywords: Bintuni Basin, Permian, geochemical, maturation, foreland basin