Antistatic composites of polyurethane, polyvinyl and natural rubber with the electriccal resistivity of 106-1010 Ωcm were prepared using tetrapod-shaped zinc oxide whisker as the condnctmg additives. The conductive behavior of this system has been analyzed and the results show that the tetrapod-shaped ZnO whisker is an effective antistatic additive, for polymer materials. A formula of critical volume fiaction of ZnO whisker for the formation of the conducting paths o1 the polymer/ZnOw composite has been put forward and compared with the experimental results. The analysis of the conductive mechanism indicates that the charge concentrating effect at the needles" tips of the whisker will be distinct if the material is under an electric field. The tunnel effect may exist and cause leakage current in this kind of composites.