Abstract: In order to overcome the limitation of qualitatively health identification for damping springs of large vibrating screen (LVS),a diagnostic methodology for identifying the stiffness of damping springs with free response was pro- posed. With the geometric position error of the damping system considered,the asymmetric dynamic model of the vibra- tion screen with damping spring fault was established and followed by deriving the vibration differential equation. Then,the discrete free acceleration response data were processed by digital filter,eliminating the trend item and nu- merical integration,and subsequently constructed in a matrix form to obtain the modified stiffness matrix. Moreover, with disassembling stiffness matrix and defining the stiffness assurance criterion,the principle and procedures for stiff- ness identification of a large vibrating screen was summarized. Finally,the validity of the developed method for stiffness identification was verified by an experimental test and the error is within 3. 56% . The research may accomplish the quantitatively health identification for the damping springs of large vibrating screen.