Fe/Pt multilayer films with an Ag, Ti or Bi underlayer were prepared by magnetron sputtering and effect of the underlayer on the magnetic properties of annealed Fe/Pt multilayer films was also investigated. Our results demonstrate that Ag underlayer has little effect on the in-plane coercivity H-c of the Fe/Pt multilayer film due to the formation of Ag and L1(0)-FePt phases in the films. The H-c of Ti/[Fe/Pt](13) film keeps on rising with the increasing annealing temperature T. up to 500 degrees C and then decreases with the further increasing T-a.. The reason should be attributed to the formation of some intermetallic compounds between Ti and Fe; Pt at a high T-a which is harmful to the structure of L1(0)-FePt. The H-c of [Fe/Pt](13) films is enhanced by the Bi underlayer, which can be understood by considering the promotion of the L1(0)-FePt phase by Bi diffusion. (C) 2007 Elsevier B.V. All rights reserved.