The nanocrystalline Ni3Fe powders were obtained via wet mechanical alloying route in argon atmosphere. As process control agent (PCA) the benzene (C6H6) was used. In order to release the internal stresses an annealing at 350 °C for 4 hours was performed. Alternatively, the nanocrystalline Ni3Fe powder was subjected to a process of incipient recrystallization at 600 °C for 30 minutes in vacuum. The recrystallised powders have a crystallite size of 30 nm. The magnetic properties (the frequencies dependence of permeability and magnetic losses) were investigated in AC field of 0.05, 0.1 and 0.2 T. It was found that the polymerization process has a strong influence over the magnetic properties of compacts. If the polymerization was performed by heating the powders into a mould, generally we observed a positive influence over the permeability but a negative influence over the magnetic losses.