The "spillover" of the Raman spectral lines and the change of their intensities were observed in a- LiIO3 single crystal under the action of a DC field. They are due to the fluctuation of the polarizability tensor and the Raman tensor of α-LiIO3 single crystal during the transportation of ions. The former induces the o←→e scattering. Sequently, if this o←→e scattering light acts as an incident beam to produce Raman scattering, the phenomena mentioned above could occur. The latter brings about the phenomena directly. The former mechanism is predominant.