In this paper, the electrical properties of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) films have been studied. Electrical characterizations were realized on the base of dc conductivity - temperature measurements together with its variation with doping ratio. The dark conductivity measurements were carried out under vacuum of 10(-5) Torr. The electrical conductivity of the polymer prepared in sandwich structure as Al/polymer/Al was measured in over the temperature range of 30 - 235 degrees C, The measurements were performed on PPO samples with thickness 6.0 mu m undoped and doped by tetra-n-butylammonium tetrafluoroborate in chloroform solution at a rate of 0.25 mol doped/mol PPO, 0.50 mol doped/mol PPO. The activation energies of the samples were determined as a function of the doping ratio.