Various compositions of Potato starch and NH4NO3 based biopolymer electrolytes have been prepared by using Solution Casting Technique. The Prepared biopolymer electrolytes are characterized by using XRD, FTIR, AC Impedance analysis etc… XRD analysis confirms the amorphous nature of the biopolymer electrolytes. The FTIR analysis reveals the complex formation between the biopolymer (Potato starch) and Salt (NH4NO3). The maximum conductivity is found to be 5.67×10-5 S/cm at ambient temperature for 30 Potato starch: 70 NH4NO3 biopolymer electrolyte among the prepared biopolymer electrolytes.