Shock Wave propagation is the key process of implosion for Inertial Confinement Fusion (ICF).α-iron is an important first wall material which have been widely researched by many authors.But its reactions under these extremely condition, like its debris effect, transition and so on, are not very clear.Here we have developed a new EAM potential of iron suitable to mimic the behavior of iron to extremely high pressure and temperature.Associate with non equilibrium molecular dynamics (NEMD) method, we could reproduce Hugoniot relationship and α-εtransition at correct pressure.We fit cold energy curve and common point defects.Our calculated melting point and phonon dispersion curve is also matched good with experiments.This shows our potential is appropriate to high temperature and pressure condition.Using our newly developed potential, we have investigated the orientation effect of iron crystalline under shock and unshocked compression, and analysised its transition path in atomic scale in detail, and find [110] shuffle mechanism which is consistence with other authors.Additionally, we design a newly local structure identified method-Pair Wise Neighbor (PWN) method to character transition product and find an interesting phenomenon that the c axis of newly produced ε-iron is not always those in the cross-section of shocking.It is apt to forming appropriate transition states within shock front and gradually relaxed to cross-section.And different orientations preferred transition states have little difference whose c-axis tempt to aligned in near [100] direction of its origin bcc lattice.Our PWN method to judge hcp atoms which is quite consistence with Acklands method is proved to be effective in this work.These findings need to be verified by experiment which may be difficult to approach at present techniques.