Dilithium phthalocyanine (Li2Pc) possesses mixed electronic-ionic conductivity due to overlap of pi-pi orbitals (electronic) and mobility of Li+ ion (ionic) in a channel formed due to stacking of the macromolecules. Electrochemical impedance measurements provide separation of electronic and ionic conductivities. The temperature dependence studies are employed for calculation of activation energies. The electronic conductivity shows a marked increase on applying dc bias voltage across a symmetrical cell of Li2Pc with blocking electrodes, whereas the ionic conductivity is marginally influenced. (C) 2005 The Electrochemical Society.