Composite materials used for electrode and electrolyte materials have been intensely studied in view of their advantages such as higher conductivity and better operational performance compared to their single-phase counterparts. The present work aims at studying the electrical and structural characteristics of a new composite electrolyte namely, (PbI 2 ) x −(Ag 2 O-Cr 2 O 3 ) 100−x where x=5, 10, 15, 20, and 25 mol%, respectively, prepared by the melt quenching technique. The room temperature X-ray diffraction spectra revealed certain crystalline phases in the samples. AC conductivity analysis for all the prepared samples was carried out over the frequency range 1 MHz-20 Hz and in the temperature window 297-468 K. The room temperature conductivity values were calculated to be in the order of 10 −5 -10 −3 Scm −1 . An Arrhenius dependence of temperature with conductivity was observed, and the activation energies calculated were found to be in the range 0.27-0.31 eV. Furthermore, the total ionic transport number (t i ) values obtained for all these indicated the ionic nature of this system.There has been a considerable interest in studying fast ion conducting solid electrolytes that exhibit high ionic conductivity at temperatures well below their melting points. The demonstration of such electrical properties by these materials make them potential candidates for various electrochemical applications viz., solid-state batteries, sensors, fuel cells, etc.[1]. It is noteworthy to mention here that among these electrolytes, although the class of AgIbased electrolytes offering promising characteristics have been fairly reported in literature [2], the scope for further exploration in this field is still wide open. The important feature that attract researchers toward such an exploration in materials with potential mobile ions as Ag + ion lies in certain inherent features of these electrolytes as their isotopic properties, ease in preparation, high room temperature conductivities, etc. More recently, the trend of replacing Ag + ions with other feasible cations in dopants like CuI, CdI 2 , etc. has been followed to realize new materials exhibiting comparable electrical conductivities and exploiting the favorable character of silver ion to electrical conduction [3,4]. Moreover, this new route adopted in developing such materials has paved the way for the "mixed cation effect" [5] wherein a second cation is involved in the process of conduction actively or by influencing conductivity via structural alterations. In view of this, the present study aims to study the effect due to varying concentrations of a new dopant salt, PbI 2 , on conductivity in the case of the system PbI 2 -Ag 2 O-Cr 2 O 3 . It is crucial to note that the network former/modifier ratio also plays a dynamic role in influencing the overall electrical conductivity. However, a study on one such similar ternary system has observed efficient values of conductivity for network former/modifier ratio of one [6]. Hence the above ratio has been maintained at 1 througho...