The solid-form corrosion inhibition mechanism and its applicability in high temperature buried pipeline protection were discussed, via the releasing rate test, inhibition effectiveness evaluation, and the electrochemical test & analysis of linear polarization, dynamic potential polarization and EIS. The results showed that the releasing time of the solid inhibitor was 33 d under the pipeline operating condition. When the concentration of solid-form corrosion inhibitor was 5 000 mg/L, the corrosion rate of T/S-52K steel can be significantly reduced, and the inhibition effectiveness was 89.16% under the simulated pipeline operating condition. After injecting the solid-form corrosion inhibitor, the polarization resistance Rp of T/S-52K steel increased rapidly, the reaction resistance of the electrode increased, the corrosion potential moved forward significantly, and the reduction in corrosion rate was obvious. The film of corrosion inhibitor played a role of corrosion inhibition mainly by blocking the cathodic electrochemical reaction. The release components of the solid-form corrosion inhibitor can form a“phase forming”film on the metal surface, and the membrane resistance Rm of the corrosion inhibitor film increased significantly with the extension of the corrosion time frame. From the simple but effective assessment method, the derived release rate and optimum dosage of solid-form corrosion inhibitor can be used as a reference for actual implementation of this type of inhibitor.