Nanocrystalline CoFeHfO thin films have been fabricated by RF sputtering method. Co52Fe23Hf10O15 thin film is observed, exhibit good magnetic properties with magnetic coercivity (Hc) of 0.18 Oe; anisotropy fild (Hk) of 49 Oe; saturation magnetization (4лMs) of 21 kG, and electrical resistivity (ρ) of 300 01cm. The frequency response of permeability of the film is excellent. The effect of microstructure on the electrical and magnetic properties of thin film was studied using X-ray diffraction (XRD) analysis and conventional transmission electron microscopy (TEM). The results showed that excellent soft magnetic properties were associated with granular nannoscale grains of α-CoFe and α-Co(Fe) phases.