In the processing of near-fault original seismic acceleration records， how to retain the real ground permanent displace ment information is a key problem to be solved in the baseline correction of seismic acceleration records. Based on the analysis and discussion of the validity and applicable scope of existing near-fault seismic acceleration baseline correction methods， this study in troduces a smooth slope displacement function model and establishes a new baseline correction method that can reasonably charac terize the permanent displacement of near-fault ground motions， and the new baseline correction method is verified by analyzing the baseline correction results of typical near-fault acceleration records. The results show that the new method established in this study improves the fitting accuracy between the displacement function model and displacement time history， reduces the influence of the selection of subjective parameters on the baseline correction results， and the corrected ground permanent displacement is in good agreement with the GPS co-seismic displacement. The ground motion baseline correction method established in this paper can not only automatically deal with the baseline drift of near-fault ground motion， but also reasonably characterize the permanent ground displacement caused by fling-step effect.