The ionic conductivity of lithium interpenetrating polymer networks has been determined by electrochemical impedance spectroscopy. The effect of different amounts of Lithium salt on the conductivity of these materials has been studied in the temperature range of 298 to 363 K. Conductivities of the order of 10(-4) S cm(-1) have been achieved. It was found that the conductivity was dependent on the amount of salt present in the interpenetrating polymer network and the maximum conductivity obtained was with a composition ratio of (LiClO4):(PEO)(88).