The thickness effects on the microstructure and soft magnetic properties of CoFeHfO thin films have been investigated in the range of 100-600 nm. There was a significant change in the coercivity (H-c) and the anisotropy (H-k) value with increasing film thickness, but the saturation induction and the resistivity almost remain unchanged. H-c and H-k reached a minimum value of 0.19 Oe and a maximum value of 50 Oe, respectively at 200 nm film thickness. The high saturation magnetic induction is 21 kG and resistivity is 500 mu Omega cm. The origin of the changing H-c and H-k values is discussed in detail based on change of microstructure along with film thickness. (C) 2007 Elsevier B.V. All rights reserved.