Improve the Finemet alloy properties by adding Ni elements, and through change the Ni content to control the composition of the alloy system, the alloy has resistance to DC bias characteristics and excellent soft magnetic properties. In the Fe79.5-XSi6B12Cu1Nb1.5Nix (X = 0, 1, 3, 5, 7, 10) alloy, increasing the content of Ni improves the amorphous forming ability of the alloy, and increased thermal stability, the soft magnetic performance has also been improved. with mu is about 10 at.% the nanocrystalline core of alloy ribbon annealed show it is about 3.4 k, and He is about 17.51 A/m. The addition of Ni is beneficial to improve the linearity of the hysteresis loop, when the amount of Ni content increases, the linearity is significantly improved, Ni10at.% alloy shows good DC bias resistance in the magnetic field. And tensile stress has also been improved linearity of the hysteresis loop, make the alloy shows good DC bias resistance in the magnetic field of 0-600 A/m. So it has constant magnetic permeability in this magnetic field, the alloys to be a kind of promising material for current transformer with direct current tolerance.