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Ketungau - Melawi Basins is located in westside of Kalimantan Island (West Kalimantan Province, Indonesia), and separated by Highland of Semintau Ridge Complex, categorized as intra-continental basin. The basin was controlled by tectonic activities during Early Cretaceous and Paleocene. Pre-Tertiary tectonics activities lead to basin configuration, which is bounded by basement high of schist and phyllite from Semintau Formation (Triassic-Jurassic age). The next Neogene tectonic activity caused Tertiary rocks folding of Silat and Tebidah Formations and created Ketungau, Silat and Melawi synclines, and Sintang anticline. Source of sediment (provenance) was came from granitic mountain belt of Schwaner and also come from High of Semintau Ridge.Stratigraphies in Ketungau - Melawi are divided in to 2 phases, Pre -Tertiary stratigraphy and Tertiary stratigraphy. Pre-Tertiary stratigraphy consist of basement rocks with age of Triassic and Jurassic recognized as Semintau Complex, which unconformable underlies with clastic sedimentary rocks Pendawan Formation with age of Cretaceous and was deposited in open marine environment (Heriyanto et al, 1993). This formation is estimated as source rock.The Tertiary stratigraphics mostly is composed of fine-coarse grained terrigeneous clastic sediment to open marine deposits rocks. The source rock was recognized in Silat Formation and Sekayak Formation, meanwhile reservoir rock had been recognized as deltaic sandstone of Early-Middle Miocene Haloq Formation.Based on paleocurrent and provenance analysis indicate that the source sequence in Ketungau- Melawi Basins was came from North particularly coming from uplift of orogenic material from Boyan mélange and Lubok Antu. Another indication is maturity level of organic which influenced by Pre-Tertiary subduction and overburden from Tertiary sedimentary. Hydrocarbon migration controlled by a Pre-Tertiary tectonic event. The trap of this basin was caused by tertiary basin inversion which causing thrust-faults. Therefore, from this data we can conclude that Ketungau - Melawi Basins have a good potential for hydrocarbon.