We have carried out the ESR study of the multiferroic triangular antiferromagnet CuCrO2 in the presence of an electric field. The shift of ESR spectra by the electric field was observed; the observed value of the shift exceeds that one in materials with linear magnetoelectric coupling. It was shown that the low-frequency dynamics of magnetically ordered CuCrO2 is defined by joint oscillations of the spin plane and electric polarization. The results demonstrate qualitative and quantitative agreement with theoretical expectations of a phenomenological model (V.I. Marchenko (2014)).