The influence of Ni content on the amorphous formability, crystallization process and soft magnetic properties of boron-rich FeSiBCuNbNi alloy was studied, the master alloy ingot was prepared by arc melting furnace, and the strip was prepared by single roll rapid quenching method. The thermal stability, phase analysis before and after heat treatment and soft magnetic properties of the alloy were analyzed by DSC, XRD, DC soft magnetic testing equipment, and the Fe78-xSi3B16Cu1Nb2Nix (x=10, 12) amorphous alloy was successfully prepared. The experimental results show that with the increase of Ni content, the amorphous formability of the alloy decreases, and the heat treatment range of forming α-Fe(Ni) single soft magnetic phase becomes narrow. When the Fe78-xSi3B16Cu1Nb2Nix(x=10, 12) alloy was annealed at 480 ℃ and 470 ℃ for 10 min, the coercivity reaches the minimum value of 6.9 A/m and 8.3 A/m, respectively; after annealing, the saturation magnetic induction of Fe68Si3B16Cu1Nb2Ni10 and Fe66Si3B16Cu1Nb2Ni12 alloys are both 1.28 T, and the initial permeability are 5.6 K and 4.8 K respectively. The linearity of hysteresis loop of Fe68Si3B16Cu1Nb2Ni10 alloy is better.