Ionic conductivities of plasticized poly(vinylchoride) (PVC)/poly(methylmethacrylate) (PMMA) blend electrolyte films containing two different lithium salts, viz., lithium tetrafluroborate (LiBF4) and lithium perchlorate (LiClO4) are studied using the AC impedance technique at 25 degrees C, 40 degrees C, 50 degrees C and 60 degrees C. A mixture of ethylene carbonate (EC) and propylene carbonate (PC) is used as the plasticizer. Pure PMMA and PMMA-rich phases exhibited better conductivity. The variation of ionic conductivity for different plasticizer contents and for different lithium salts is reported. The variation in film morphology is examined by scanning electron microscopic examination. Finally, the existence of ion-ion pairs has been identified using Fourier Transform infrared analysis (FT-IR) measurements.