According to the concept of pipeline performance design, the current seismic code for oil and gas pipelines stipulates that the displacement of fortified faults in important sections and general sections are the predicted maximum displacement and average displacement, respectively. However, at present, the fault displacement estimation method generally gives only the maximum displacement of the fault in the next 100 years, but not the average displacement. Therefore, based on the investigation results of co-seismic dislocation distribution of seismogenic faults on the surface at home and abroad, the distribution characteristics of co-seismic dislocations along the surface fracture trend of the fault are summarized and analyzed in this paper. And then the ratio of the average co-seismic dislocation of the fault to the maximum co-seismic dislocation of the fault is summarized by the statistical comparison and analysis of the average displacement obtained by different calculation methods in the actual earthquake cases. Anyway, based on a large number of data of seismic fault displacement at home and abroad, considering a certain safety factor, this paper suggests that 2/3 of the maximum displacement of the predicted fault should be used as the fortification displacement of the oil and gas pipeline in general sections.