A micro-porous poly(vinylidenefluoride-co-hexafluoropropylene)[P(VDF-HFP)]-based electrolyte (MPE) is prepared by the phase inversion technology using N, N-dimethyl formamide (DMF) as solvent and distilled water as non-solvent. In order to enhance the porosity of polymer membrane, glycerin is added to the polymer solution as plasticizer as well as non-solvent. Various amounts of alumina (Al 2 O 3 ) nanoparticles are used as fillers in the preparation of porous polymer membrane. The crystallinity of polymer matrix decreases with addition of Al 2 O 3 nanoparticles and the amorphous phase expands accordingly. The resulting MPE has 2.11×10 −3 S·cm −1 of ionic conductivity, 0.66 of the lithium ions transference number and 4.816 kJ·mol −1 of the activation energy for ions transport when the polymer matrix contains 10% of the mass fraction of Al 2 O 3 nanoparticles. Effect of Al 2 O 3 on the electrochemical properties of polymer electrolyte has been investigated in this paper. Analysis of FTIR spectra shows that there is an interaction between Al 2 O 3 nanoparticles and CF bonds of polymer chain.