With the increasing complexity of prospecting objectives，reverse time migration (ＲTM) has attracted more and more attention due to its outstanding imaging quality． ＲTM is based on two- way wave equation， so it can avoid the limits of angle in traditional one- way wave equation migration，image reverse branch， prism waves and multi- reflected wave precisely and obtain accurate dynamic information． However，the huge demands for storage and computation as well as low frequency noises restrict its wide application． The normalized cross- correlation ima- ging conditions based on wave field decomposition are derived from traditional cross- correlation imaging condition， and it can eliminate the low- frequency noises effectively and improve the imaging resolution． The practical proce- dure includes separating source and receiver wave field into one- way components respectively，and conducting cross- correlation imaging condition to the post- separated wave field． In this way，the resolution and precision of the imaging result will be promoted greatly．