Abstract: Severe nonlinearity is one of the main obstacles for elastic full-waveform inversion (EFWI),which is caused by the complexity of elastic wave propagation.Based on the finite-difference elastic wave simulation method,we analyzed the behavior and nonlinearity of different objective functions with respect to elastic parameter perturbation scales in velocity,impedance and Lamé parameterizations,especially the evolution of L₂ norm objective function calculated by seismic data in different offsets with respect to P-wave and S-wave velocity perturbation scales.The analysis results will provide some theoretical guidance for EFWI to implement the multi-step and multi-scale inversion strategy.