This paper investigates the sputter gas (Ne, Ar, and Kr) influences on magnetic properties of Fe/SiO2multilayer film. The magnetostriction changes due to Fe layer thickness are strongly dependent on sputter gas species. This phenomenon cannot be explained only by Fe crystal orientation change. X‐ray photoelectron spectroscopy analysis indicates the magnetostriction change is also related to the Fe–Si‐O mixed state formed between Fe and SiO2layers, and to the thickness of the region. Ne improves the soft‐magnetic properties of Fe/SiO2film, but Kr deteriorates the properties. This result is thought to be caused by the difference in magnetic anisotropy dispersion due to Fe crystal grain size. Saturation magnetization of 1.72 T, hard‐axis coercivity of 0.3 Oe, and relative permeability (at 5 MHz) of more than 5000 are achieved under nearly zero magnetostriction in Ne80Ar20ion‐beam‐sputtered Fe/SiO2(10/2.5 nm) film, with no post annealing.