This study aims to explore the durability issues regarding chloride ion corrosion of concrete structures,and further investigates the modified supplementary cementitious material(MSCM) which acts as a significant enhancer of performance of mortar and concrete. The composition of MSCM includes mineral slag powder, fly ash and inhibitor. The microstructure, sulfate erosion resistance and electric flux of high-performance concrete are tested with MSCM, and the results show that the pore structure of concrete is improved significantly along with excellent electrochemical performance. It is observed that the substantiality of concrete after being mixed with 18%(mass fraction) MSCM is enhanced effectively. The sulfate resistance coefficient of concrete is found to be greater than 1.2, and the electric flux of concrete is less than 600 C. These results have demonstrated that the MSCM possesses an excellent electrochemical performance and a wide applicative prospect in marine environment. This study aims to explore the durability issues regarding chloride ion corrosion of concrete structures, and further investigates the modified supplementary cementitious material (MSCM) which acts as a significant enhancer of performance of mortar and concrete. The composition of MSCM includes mineral slag powder, fly ash and inhibitor. The microstructure, sulfate erosion resistance and electric flux of high-performance concrete were tested with MSCM, and the results show that the pore structure of concrete is improved significantly along with excellent electrochemical performance. It is observed that the substantiality of concrete After being mixed with 18% (mass fraction) MSCM is enhanced effectively. The sulfate resistance coefficient of concrete is found to be greater than 1.2, and the electric flux of concrete is less than 600 C. These results show that the MSCM possesses an excellent electrochemical performance and a wide applicative prospect in marine environment.