The solid polymer electrolytes (SPEs) composed of Poly (ethylene oxide) (PEO) with sodium trifluoromethanesulfonate (NaCF3SO3) salt has been prepared by solution casting technique. The conductivity and dielectric of the solid polymer electrolyte systems were studied within the broad frequency range of 50 Hz–1 MHz and within a temperature range of 30 ËšC to 100 ËšC. The samples were prepared by various salt concentrations ranging from 2 wt% to 22 wt%. The sample containing 18 wt% of NaCF3SO3 salt exhibit the highest ionic conductivity of 1.091 x 10-5 Scm-1 at 30 ËšC. The conductivity of the SPEs has been found to depend on the salt concentration that was added to the sample. When higher salt concentration was added, ionic conductivity decreased due to the association of ions. The temperature of conductivity from 30 ËšC to 100 ËšC of SPEs was found to obey the Arrhenius rule. The dielectric permittivity decreased rapidly towards high frequencies due to the electrode polarization effects.