Calculations have been carried out to determine the effect of Fe-Ni-Co-V alloys on fusion reactor neutronic performance. The radiation damage in the first structural wall and the tritium breeding ratio were calculated as a function of alloy composition using the tritium breeding blanket module of the Experimental Power Reactor as the reference design. The atomic displacement rate was found to be approximately constant for all alloy combinations. However, the gas production and tritium breeding exhibit reasonably large variations (∼20%) as the cobalt concentration is increased in the alloy.