Two molar ratios, namely 50%-25%-25% and 70%-15%-15% of the compound AgI-PbI2-CsI is prepared and the impedance measurements are made. The recorded impedance and admittance data are analysed in the moduIus as well as permittivity formalisms. The system seems to have grain boundary effect and becomes highly diffused due to the electrode effect around 235 degrees C.