Summary: Fine ductility, larger cycle of low cycle fatigue and the ability of higher rate of strain hardening are the advantages of low yielding steel (LYS). It is used to develop a new seismic resistance device of added damping and stiffness. To overcome the local fracture problem on steel plate, a newly designed rhombic type steel plate with low yielding steel is developed. The relationship between stress and strain after yielding of LYS is different from ordinary steel. Therefore, the double linear model for A36 steel energy absorber cannot accurately reflect the energy dissipation behavior of LYS under reciprocating loading. In order to simulate the complicated nonlinear strain hardening behavior of this newly developed device under reciprocating loading, the Wen’s model is revised and extended. The principle of statistics is then used to develop the procedure and criteria to demonstrate the correctness of this revised analytical model. The statistical analysis results and the comparison between numerical simulation and experimental data reveal that the modified Wen’s model, proposed in this research, is truly suitable for simulating the hysteresis energy dissipation behavior of rhombic low yielding steel plate.