Oil reservoirs, after exploration and drilling production wells, at first, start to produce by natural reservoir forces, but the reservoir pressure gradually declines, and some methods will be needed to maintain the reservoir pressure. Finally, if the residual oil is not recoverable by reservoir pressure maintenance methods, the residual oil in the reservoir will be minimized by changing the reservoir properties, using the specific EOR methods. The water/gas- based methods are common in EOR methods. In the industrial studies on candidate base reservoirs, usually the function of EOR methods is explained separately and the technical and economic studies of the methods with the approach of the short-term and long-term investigation, have not been done simultaneously. In this research, at first, the most appropriate EOR methods were determined using software screening, and their dynamic simulation was performed on the initiated model. Then, the economic model calculations were performed according to production and injection profiles in order to obtain the optimum technical and economic method. Results show that the immiscible gas injection method will have a greater NPV than the water-based method by increasing the injection time and changing the production control parameter.