The permittivity of a rice (Oryza sativa L. japonica)-cell suspension was measured in the frequency range from 0.2 to 20 MHz. A good linear correlation (=r) of 0.999 was observed between the permittivity at 0.41 MHz and the cell density, Permittivity was lost as a result of cell destruction by aging, ultrasonication, or boiling, From a comparison between changes in the permittivity of the cell suspension and freezing curves obtained by differential scanning calorimetry; the major freezing injury was believed to be due to damage to the plasma membrane. Freezing damage was measured by the intact cell ratio calculated from the permittivity and 2,3,5-triphenyltetrazolium chloride (TTC) reduction viability assay under various freezing conditions. The effects of changes in the concentration of dimethylsulfoxide used as a cryoprotectant and in the Fooling rate showed similar trends for the intact cell ratio and TTC viability, although there was a quantitative discrepancy between them.