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The frontier Lengguru Basin is located in West Papua adjacent with the prolific Bintuni Basin. Previous studies agreed that petroleum plays may occur in mesozoic sequence in this area. However, poor understanding of the petroleum system in this basin has caused the exploration activity to be still considered as frontier. Hence, integrated data in mesozoic sequence is necessary to give better understanding of the petroleum system in this area. This study uses measuring section data in five traverses that were followed by laboratory analysis including 53 thin sections analysis to understand facies, depositional environment and diagenesis of each sequence. These interpretations were integrated with structural and geochemical data including paleostress, Total Organic Carbon (TOC) and RockEval Pyrolisis. Mesozoic sequences from the oldest to youngest are Kopai, Woniwogi, Piniya, Ekmai and Imskin Formations. Overall, the Lengguru area experienced transgression sequence, although there were regression phases that are characterized by beach-shallow marine sandstone of Woniwogi and Ekmai Formations. Diagenetic events in these sequences are comprising compaction, cementation by calcite, quartz, clay minerals and iron oxides, dissolution and alteration of unstable grains into kaolinite and tectonic fracturing. Six paleostress directions were identified, comprising of WNW-ESE, NNW-SSE, N-S, NNE-SSW, NEE-SWW and E-W that were formed in pure strike-slip regime from Miocene to Pliocene. The primary source rocks are Kopai, Piniya, Ekmai, and Imskin Formation with the highest organic content is Ekmai Formation which the TOC’s content is up to 17.65%. Quartz sandstone, sandstone and limestone facies from Woniwogi, Ekmai and Imskin Formation respectively may serve as reservoir candidates with the sand-limestone shale ratio up to 100%. These formations have good porosity up to 13% that are predominance by secondary porosity comprising dissolution and fractures. The seal candidates are intraformational shale, mudstone and crystalline limestone of Piniya, Ekmai and Imskin Formation respectively. The traps are possible associated with giant anticline and thrust faults complex in this area.