For the MOS capacitance with the ultra thin hafnium oxide, an equivalent four-element circuit model including the additional series resistance and series inductance is proposed to be employed in the two-frequency C-V correction. These extracted parameters by independently measuring the capacitor at two different frequencies eliminate the frequency dispersion at high frequencies. The corrected C-V curves agree with the theoretical calculation very well. The parameters are extracted, and the relationships between the components’ values, the capacitance area and the inversion layer thickness are also presented in the paper. Experimental and theoretical results show that the model can be incorporated in the routine C-V measurement procedure and provide more accurate data.