Studies of synergetic irradiation effects and liquid lead-bismuth eutectic(LBE) corrosion/embrittlement effects on ferritic/martensitic(F/M) steels are of great importance for developing high power spallation neutron targets(>1 M W) such as the European Spallation Source(ESS) and Accelerator Driven System(ADS) facilities that can be used for transmuting long-lifetime radioactive wastes. Liquid LBE(45Pb-55Bi,in terms of mass fraction) has been selected as the candidate target material in high power spallation neutron targets due to its favourable thermal,physical & chemical properties,and to its high spallation neutron yield. 9Cr F/M steels such as T91(9Cr1M oVNb,in terms of mass fraction) have been chosen as the structural material for the targets due to their good mechanical properties and good resistance to irradiation induced swelling in fission neutron irradiation environments. For developing high power spallation neutron targets,behaviors of F/M steels in spallation neutron target irradiation environments and LBE corrosion/embrittlement effects have been extensively studied. However,many open questions have not been answered. The aim of this paper is to describe the present research situation on this topic. The obtained experimental data about LBE embrittlement effects on F/M steels is summarized and the influence of different parameters involved is analyzed to understand the influence effect on LBE embrittlement effect of F/M s.