Using the commercial code ANSTS/LS-DYNA, this study has established a Split Hopkinson Pressure Bar (SHPB) finite element model (FEM) of X70 pipeline steel. Moreover, the stress-strain behavior of X70 pipeline steel has been investigated by a simplified Johnson-Cook model. The stress and strain relationship of X70 pipeline steel under different compact speeds is obtained under the high strain rate of 103S-1. The results obtained by numerical simulation agree well with those by experiments, and the parameters of Johnson-Cook model describe accurately the mechanical behaviors of X70 pipe line steel under high strain rate. This conclusion will serve as an important reference for developing and applying materials.