This paper propose a LEAN design and LEAN approach for project development of Mobile Production Facility (MPF). The Mobile Production Facility (MPF) is the well known facility developed in onshore oil and gas field for mature field which the field development plan has extended to remote areas which contain small marginal oil prospects. The LEAN design for Mobile Production Facility could improve the economics of onshore oil and gas projects development by reducing capital expenditure (CAPEX) and project development lead times and increasing flexibility for production planning through the mobilization design, and be a key factor in the economic exploitation of both marginal and mature fields. Insight gained through in-house design, international code & standard, and package design experts led to the development of the LEAN Mobile Production Facility proposed in this paper. Discussion include a characteristic of a reference oilfield, project background, application of Mobile Production Facility, the innovative design of package and equipment leading to lower CAPEX in detail, as well as the benefits and limitations of the LEAN Mobile Production Facility. Areas of future project development in support of LEAN Mobile Production Facility are identified, including the potential to unlock the further marginal reserves.