For linear parametric system, like mass proportional damping case, physical parameter identification of horizontal layered soil and inversion of ground motion of bedrock are done by using the Least-squares-based hybrid inversion algorithm. For nonlinear parametric system, such as Rayleigh proportional damping case, the modified Levenberg-Marquardt (mLM) method is introduced. Since the mLM method is sensitive to the initial values of parameter, a SVD-mLM method is proposed with combination of singular value decomposition (SVD). Parameter identification of nonlinear parametric system and inversion of ground motion are performed by using the SVD-mLM-based hybrid inversion algorithm. The numerical simulation results show that the identified parameters of horizontal soil layers and inversed ground motion of bedrock have high precision, and the proposed method is useful for geotechnical engineering and robust on noise.