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[en] Conduction mechanism in Fe_2O_3 doped Na_2O·Bi_2O_3·B_2O_3 semiconducting glass system was studied in frequency range 10 Hz to 1 MHz and at temperatures between room temperature and 663 K. The total conductivity spectrum follows universal power law with frequency exponent ‘s’ value less than unity and lies in the range 0.51≤s≤0.78. These ranges of ‘s’ values indicate that the carrier transport is predominately due to hopping electrons between charged defects and show temperature dependence as predicted by correlated barrier hopping (CBH) model. The change in activation energy of dc conductivity with temperature reveals the change in conduction mode from small polaron hopping (SPH) at high temperatures (T>θ_D/2) to variable range hopping (VRH) at low temperatures (T<θ_D/2). The range of density of states at Fermi level N (E_F)=7.25×10"2"1–1.32×10"2"1 eV"−"1 cm"−"3 at temperatures below θ_D/2 corresponds to localized states near Fermi level. The large values of activation energy W_2 (0.067–0.155 eV) dominated the conduction may results in high range of temperature (T=503– 423 K) for variable-range hopping conduction in these glasses.