Conventional inhibitors could not effectively control the hydration of clay surface，which caused wellbore instability. An intercalation adsorption inhibitor with high temperature resistance was prepared by introducing sulfonic acid group into tetraethylene pentamine as reaction monomer. The structure of the inhibitor was characterized and its performance was evaluated. The mechanism of intercalation adsorption inhibitor with high temperature resistance was further analyzed. The results showed that there were a lot of strong adsorption groups and hydrophobic groups in the molecular structure of new inhibitor，which had low molecular weight， non-toxic environmental protection and good thermal stability. The analysis of inhibition mechanism showed that the electrostatic repulsion and short-range repulsion of clay surface hydration could be effectively reduced by the combination of strong adsorption group and exchange of hydrated sodium ions. By reducing the surface tension of aqueous solution and changing the wettability of clay，the self-imbibition capacity and specific hydrophilicity of shale could be controlled，and then the invasion of water phase was reduced. Meanwhile，the new inhibitor had strong adsorption and anti-desorption ability，which could adsorb on the clay surface for a long time，improve the hydrophobicity of the clay surface，and reduce the invasion of free water. The new inhibitor had good properties of inhibiting mud production，controlling clay hydration expansion and preventing shale dispersion，which was superior to polyamine inhibitors at home and abroad.