A method to solve sulfate corrosion damage of recycled aggregate concrete(RAC) from the wet-dry cycles test~used to study material performance degradation rules for all RAC(r=100%)and RAC with different recycled aggregate replacement ratio ( r)under sulfate environments 3%,5% and 10%(by mass) Na₂S0₄. The results show that:①linear dilatation ratio(ΔL)of RAC increases with the increase of r, and the change trend of relative dynamic modulus of elasticity ( E_r) were consistent, and the attenuation rate for E, increases with the decrease of r under different r and 5 %(by mass) Na₂S0₄;②the attenuation rate of E_r and the ΔL for the all RAC increase with the increase of the level of Na₂S0₄ solution concentration;③the specific value of E_max( r ) /E, close to 1.07. At the same time, the damage computation model of RAC in sulfate environment was put for- ward based on test results.