Blended polymer electrolyte of methylcellulose (MC) / chitosan were prepared with different weight percentage of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BMIMTFSI) via solution casting technique. The film was characterized by impedance spectroscopy to measure its ionic conductivity. Samples with 45% of BMITFSI exhibit the highest conductivity of (1.51 ± 0.13) × 10-6 S cm-1at ambient. Dielectric data were analysed using complex permittivity and complex electrical modulus for the sample with highest conductivity. Dielectric data proved that the increase in conductivity is mainly due to the increase in number of charge carriers.