Through the analysis of the core imbibition experiment results of natural core and artificial core, the existence of clay mineral has an influence on imbibition. Using glass tubes to fill different proportions of clay minerals and quartz sand, visually observe and measure the amount of wet phase replacement and gas-liquid leading edge penetration rate. The experiment used 2%, 3%, 5% content of clay minerals and pure quartz sand as a comparison to find, The pure quartz sand wet phase replacement amount is 88.96%, and the 5% content clay mineral wet phase replacement amount is 69.22%. When the clay mineral content is 5%, the replacement time required is 2.29 times that of pure quartz sand, and the amount of wet phase replacement is 77.8% of pure quartz sand. Clay minerals swell after contact with deionized water, and the amount of wet phase replacement decreases with increasing clay mineral content. Adding KCL to the wet phase can effectively inhibit the expansion of clay minerals and increase the replacement rate of the wet phase. The experimental results show that in the 5% clay mineral filled tube experiment, the 4% concentration of KCL solution is added to the wet phase, and the final wet phase replacement rate is close to pure quartz. Sand wet phase replacement rate.