The high temperature soft magnetic properties of Fe85.2Zr3.5Nb3.5B6.8Cu1 amorphous and nanocrystalline alloy were investigated. A Hopkinson peak was observed in the amorphous alloy, which was not observed in the nanocrystalline alloy, and this has been explained by the combination of the anisotropy reduction and the deterioration of magnetic properties. A rapidly decrease in permeability at the Curie temperature of amorphous (T-c(am)) was observed in amorphous and partial crystallized nanocrystalline alloys, this phenomenon was disappeared in the highly crystallized nanocrystalline alloys, which was illustrated by the intergrain exchange magnetic coupling through a thin amorphous layer in the two-phase nanocrystalline alloy. (C) 2004 Elsevier B.V All rights reserved.