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JN field is located in the northern part of South Sumatra Block, Indonesia. This field was discovered in 1985 and started producing in 1986. Water injection as pressure maintenance was implemented just one year after initial production, with gas lift used as the artificial lift system. As the water injection was able to provide negative voidage, the reservoir pressure began to increase, eventually enabling the wells to start to flow naturally again in 2007. In 2013, as the water cut increased to an average value of 97%, the field encountered two main problems, i.e. natural flow ability and water injection capacity to keep the voidage replacement ratio at the optimum value. Several naturally flowing wells began to ceased to flow, and the field production sharply declined to only 350 bopd at the end of 2013. By considering the existing field capacity, estimated additional recoverable reserves, and cost impact, field optimization plans were carried, with two main objectives: to optimize water injection and to install new artificial lift. The scenario for water injection optimization was intended to maintain oil production from the wells that were still able to flow naturally by focusing the injection on a specific region, restoring injection capacity at the low injection well, and adding water supply to the system. ESP was installed at the shut-in wells that still had considerable remaining reserves and offered significant gain to the additional investment required. The integration between above subsurface plan with facility engineering design and operational capability led to a 750 bopd oil gain and was able to arrest the rapid production decline in JN field. This paper will elaborate on the case study of revitalizing oil production on JN field, starting from problem identification, action taken, challenges and process integration during implementation, final result and future optimization plan for this field.