One of the methods that has recently received attention in oil recovery and the topics of increased extraction is foam injection in the tank, which partially improves the defects of the mixed and non-mixed gas injection method and leads to more oil recovery. Based on the main goal of foam injection and the characteristics of the reservoir fluid and rock, it is necessary to design its structure and type. One of the most important parts of these designs is choosing the appropriate surfactant. Foam injection can be done with the aim of delivering the surfactant to the oil inside the matrix and reducing the surface tension between the gas and oil. In this case, with the reduction of capillary forces, the existing balance between capillary and gravity forces will be more in favor of gravity forces, oil recovery will be increased. In this paper, oam Injection into an oil carbonate reservoir to increase the viscous forces against the capillary forces will be discussed.