Fermi resonance is one of the general and important phenomena in vibration spectra.The method of solvent variation is one of the main methods to study Fermi resonance.In the present paper,FTIR spectroscopy was used to study the Fermi resonance of p-benzoquinone in thirteen solvents.The results show that there are some function relationships between the dielectric constant of solvent and the intensity ratio of Fermi resonance.And the empirical formula was obtained by curve fitting.The equation of Kirkwood-Bauer-Magat was applied to the study of Fermi resonance.And the authors obtained the relation between the intensity ratio R and the dielectric constant ε.This result is in accordance with the empirical formula.In order to confirm our result,the infrared data of R.A.Nyquist and J.K.Seehra were analyzed.These results are in accord with that of p-benzoquinone.