Obiective To study the changes of biomechanical properties of human cornea after LASIK and to predict corneal stiffness after surgery. Method The corneal tangent stiffness coefficient (S_TSC) and energy absorbed area (A_absorbed) were calculated by the result of corneal visualization scheimpflug technology(Corvis ST). The changes of corneal stiffness and viscosity after refractive surgery were analyzed. Result The difference of corneal S_TSC and A_absorbed before and after LASIK has statistical significance (P<0.05). The formula for predicting corneal stiffness after refractive surgery is: S_before_surgery= 1.055bIOP_before_surgery+ 0.015CCT_before_surgery,S_{after surgery}= 0.937S_before_surgery+0.019CCT_{after surgery}. Conclusion Refractive surgery not only changes corneal thickness, but also reduces corneal stiffness and viscosity. Prediction of corneal stiffness after surgery is helpful for clinical study of corneal posterior surface anterior protrusion and Surgical Cutting Quantity.