The transparent glasses of composition 40P₂O₅-20ZnO-(40-x)Na₂O-xLi₂O have been prepared using conventional melt quenching technique (where 0 ≤ x ≤ 25 Li₂O mol. %). The amorphous nature of the prepared glass samples is confirmed by x-ray powder diffraction (XRD). By increasing the Li₂O content, the density and oxygen packing density increase while the molar volume decreases which indicates that the structure is more compact. The differential thermal analysis (DTA) studies showes that 15 mol.% Li₂O glass sample has the highest thermal stability and the glass transition temperature (T_g) decreases as the content of Li₂O increases till 25 mol.% Li₂O . The ac and dc electrical conductivities and dielectric constants of the prepared glass samples have been investigated. It is found that the          dc conductivity increases with the concentration of Li₂O mol.% and the temperature dependence of the dc conductivity at low temperature (303 – 383 K) and at high temperature (403 – 473 K) obey the Arrhenius law. The activation energies ΔE_dc1 (at high temperatures) and ΔE_dc2 (at low temperatures) were determined. The values of σ_dc can be obtained also from the impedance study at different temperatures and different concentrations using Cole-Cole plot. To determine the conduction mechanism, the ac conductivity and its frequency exponent (s) have been analyzed by correlated barrier hoping model (CBH). It is found that s has values between 0.89-0.996; consequently. The correlated barrier hopping (CBH) seems to be the most interesting model related to the obtained results. Real and imaginary parts of dielectric constant (ε' and ε'') have been found to decrease with increasing frequency and temperature and this result would be discussed by means of dielectric polarization mechanism of material. The maximum value of the maximum barrier height W_m obtained from Guitini equation was found to increase with increasing of Li₂O mol. %.