Abstract: The eastern branch of the East African Rift System belongs to an intracontinental rift basin group formed during the Cenozoic. The South Lokichar Basin is located in the north of Kenya. Since 2012, 8 oil fields have been discovered here, with 2C resource being 766 million bbl. Through integrated study of seismic, well and other geological data, we investigated the petroleum geological features and developed reservoir-forming rules. The basin has small-scale, mono-faulted structural characteristics, faulting to the west and overlapping to the east. In the western steep-slope zone, there are mainly structural-lithologic combination traps, and in the eastern gentle slope zone is structural traps. Depositional fill is characterized by a river-(fan) delta-lacustrine sedimentary system, presenting a cycle of initial rifting stage-expanding stage-waning stage. There are two sets of plays, one is Oligocene-Lower Miocene combination and the other one is Middle-Lower Miocene combination. Based on the analysis of discovered fields in the South Lokichar Basin, it was determined that mature source rocks, significant reservoirs and reasonable positioning of accumulation elements were the main controlling factors in the eastern branch rifts. The exploration potential of the eastern branch rift system was analyzed through comprehensive interpretation of gravity, seismic and depositional thickness data. The most favorable targets deserving attention are the Kerio Valley Basin to the south of South Lokichar Basin, the northwest onshore of the Turkana Basin and the Kerio Basin.