Naturally immersion in 3% NaCl solution and fast freeze-thaw were tested for the air-entrained high-performance concrete. Contents of chloride ion in concrete and relative dynamic elastic modulus after different freeze-thaw cycles were investigated.According to the principle of damage mechanics,the relationship between the freeze-thaw damage and chloride diffusion coefficient,freeze-thaw cycles are studied.Test result indicates that the freeze-thaw cycle leads to degradation,and increases the chloride diffusion coefficient of concrete.The diffusion coefficient is 1 time of undamaged concrete when the damage degree is 5%.The relationship between the damage degree of freeze-thaw,chloride diffusion coefficient and freeze-thaw cycles conforms to the exponential relationship.