One of the most important ways to enhance oil recovery in oil reservoirs is chemical flooding. The study of performance and efficiency of these processes in increasing the range of oil recovery from reservoirs depends on several factors, including the rock and fluid properties of the reservoir, and therefore one of the most important steps in evaluating the performance of these methods for a reservoir is the laboratory study and calculating the chemical agent potential to recover oil. For this purpose, a laboratory study and integrated simulation in order to identify the effective mechanisms in the injection of smart water polymer in order to identify the necessary and dominant conditions of this method was performed to improve the recovery of Iranian carbonate reservoirs. Initially, four injection scenarios, water injection-polymer injection-smart water injection, water injection-smart water injection-polymer injection, water injection-smart water polymer injection and smart water injection- smart water polymer injection were tested in a laboratory and then simulation of smart water polymer flooding using Eclipse simulator 100 and the effect of polymer injection on oil recovery and oil trapping in the reservoir rock was performed and finally the results of the simulator and the results of laboratory data were validated. The results showed that smart water injection- smart water polymer injection have better performance in improving secondary oil recovery by 63.45% and wettability changing is one of the main mechanisms to improve oil recovery. The results also showed that in optimal conditions, despite the mechanical degradation of the polymer, initial oil in place recovery is achieved up to 85% by controlled adsorption of polymer on the rock surface.