The average permeability of high salt oil reservoirs in Bohai is relatively high, and conventional polymers have poor salt tolerance. In order to improve the salt resistance of polymers and enhance the oil recovery and precipitation effect of oil displacement agents, the influence and mechanism of sodium silicate on polymer salt resistance in high salt reservoirs were studied through viscosity and scanning electron microscopy tests, combined with physical simulation evaluation methods. The results indicate that under low mineralization conditions, the viscosity increasing ability of ordinary polymers is greater than that of salt resistant polymers. As the concentration of sodium silicate increases, the viscosity of the polymer gradually increases. In different dosing methods, the initial viscosity of the "polymer+sodium silicate" system is lower than that of the "sodium silicate+polymer" system, and the viscosity difference between the two after shearing is not significant. The polymer molecule is a network structure, the inorganic gel is a flocculent structure, and the "polymer+sodium silicate" is a more dense network structure. During the experimental process of permeability characteristics, compared to a single polymer solution, the "polymer+sodium silicate" system showed enhanced sealing ability. As the concentration of sodium silicate increases, the resistance coefficient of the composite system increases, and the residual resistance coefficient first increases and then decreases. The research results and understanding provide experimental basis for the optimization of chemical formula composition and process parameter optimization technology decision-making required to improve the deep liquid flow diversion effect of target reservoirs containing polymer control and flooding agents.