In this paper the results of DC-conductivity investigation of 1,4-cis-polybutadiene thin films doped with 5% weight of silicon carbonate (SiC) of nanocrystalline form with the size of grains being about 20 nm are presented. The aim of the study was to receive a knowledge about the electrical properties and DC-conductivity mechanisms depending on film thickness, temperature and electric field magnitude. The investigated films thickness ranged from 1 to 12 mu m. The investigations were carried out for both undoped and doped with nanocrystalline SiC polymers. The current flow through the material bulk changed from 10(-12) to 10(-4) A with applied electric fields of 0 to 3 x 10(7) V/m and temperature of the film varying from 15 to 325 K. It was observed that the magnitude of the current flow through the investigated material bulk is governed by a phase state of the polymer and the presence of SiC in the bulk. The charge transport through the material bulk is controlled by the Poole-Frenkel phenomenon as well as by hopping. The determined activation energies were between kT and 0.36 eV. (C) 2009 Published by Elsevier B.V.