South Sudan Petroleum industry is fairly mature, however; updates about the status of the industry remains limited, the literature has provided little on some of the aspects of the industry related to production and petroleum reserves, this study aims to evaluate petroleum production performance and remaining reserves in Dar Petroleum Operating Company (DPOC) oilfields in block 3 & 7; examined over a period of ten years; starting from 2011 to 2021, this is expected to shed some light on the subject; and provide recommendations for further research. Method applied; is the collection of secondary data related to production, reserves and information; necessary to support the analysis; sourced from Ministry of Petroleum depository; and from the Joint Operating Company , which was used in quantitative analysis; and presentation afterwards, it was found that the production profile and forecast could only be improved by introducing oil enhancement technologies; to improve Recovery Factor (RF) from about 23% to around 33%; which could make up approximately one third of the Discovered Petroleum Initially in Place (PIIP) as per the best industry practices. And that; exerting more efforts on exploration in the areas not properly covered earlier; could replenish the reserves in addition to annual petroleum resources review that has achieved some addition recoverable volume of 81.72 MMstb. Over the years covered by the study scope. The limitation of the research was the lack of data about of reasons related to quick decline of production after the resumption and reinstatement of production in April 2013 connected to the sudden decline in production after 2013 resumption.

Keywords : Estimated Ultimate Recovery (EUR), Petroleum Initially in Place (PIIP), Petroleum Resource, Production Volume, Reserve, Processing, Recovery factor (RF), Remaining Petroleum Reserves