In order to research the effect of liner’s structure on shaped charge jet after petroleum perforating charge exploding, the formation mechanism of shaped charge jet was analyzed,and numerical simulation of the jet formation process was made with the explicit dynamic finite element analysis program. And numerical calculation of the influences of the structural parameters ( such as cone angle,well thickness) and shape of liner on shaped charge jet were made,the relations between the velocity of jet head and the structural parameters of liner were found. The results showed that for the jet formed by shaped charges with different cone angles the shape of jet head has only a little difference while the velocity of jet head greatly changes differ from each other,for shaped charges with same cone angle the velocity of jet droops with the well thickness of liner increasing,when the shape of liner is horn the velocity of jet head is the highest.