Various Fe-M-Si-B amorphous alloys were prepared by the single roll technique. Magnetic permeability and its thermal stability were investigated. Crystallization temperature, Curie temperature, saturation magnetization and effective permeability up to 1 MHz were measured. The effective permeability of 2 multiplied by 10**4 was obtained at 1 kHz for alloys with low magnetostriction of the 10** minus **6 order, which is comparable to the value of zero magnetostrictive Co-based amorphous alloys. Disaccommodation and thermal variation of magnetic permeability were also measured. Good thermal stability in magnetic permeability is discussed in terms of induced magnetic anisotropy and magnetostriction.