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The ratio of the ultimate recoverable reserves of an oil and gas field to its original geological reserves is called the recovery factor. There are many factors that affect recovery rates. Generally speaking, the first category consists of internal factors – those that are influenced by the inherent geological characteristics of the oil and gas reservoir ； The second are external factors; any factors that are influenced by the development strategies and technical measures adopted by the operator regarding the oil and gas reservoirs are considered external factors. Internal factors play a dominant role; good reservoirs always have a higher recovery rate than poor ones. During development, the appropriate layout and effective engineering measures applied to the oil and gas reservoirs can also modify the inherent geological characteristics of those reservoirs, thereby increasing their recovery rate. (1) Intrinsic factors of oil and gas reservoirs: The type of oil and gas reservoir, such as structural, faulted, lithological, and fractured oil and gas reservoirs ； The pore structure of the reservoir, such as wettability, connectivity, porosity, permeability, and saturation levels ； Natural reservoir capabilities, such as reservoir pressure levels, the presence of a gas cap, and the degree of activity of natural energy in the edge and bottom waters ； Properties of oil and gas, such as the density of oil and gas, the viscosity of crude oil, the oil-to-gas ratio, the composition of natural gas in gas fields, and the content of condensate. (2) External factors of oil and gas reservoirs: The choice of development method, such as whether to use production methods or water injection or gas injection for oil fields, and whether to use production methods or dry gas reinjection for condensate gas reservoirs ； Reasonable well pattern density and proper stratification ； The level of drilling and production technologies, along with appropriate and effective measures to increase production, such as water injection, drilling in wells with complex structures, acidization, fracturing, etc ； Three oil recovery techniques employed to improve oil field recovery rates, such as polymer flooding, chemical flooding, and thermal flooding ； Economic viability involves economic models, oil prices, investment costs, operating costs, extraction duration, and the economic limits of production volume.