Here we report the dielectric permittivity and transport mechanism of nanocrystalline metallic Fe-ZrO2 solid solution synthesized by high energy ball-milling method in the temperature range 298-523 K and in the frequency range 20 Hz-1 MHz. Formation mechanism, structural and microstructural changes of different phases and relative phase abundances have been estimated by Rietveld analysis of XRD patterns. The direct current conductivity study shows decrease in activation energy with increase in iron percentage. The adiabatic small polaron model is found to govern the dc transport process throughout the temperature range. Alternating current conductivity is found to follow the power law sigma(-1)(f,T)= f(s)T(n). A transformation from small polaron hopping to correlated barrier hopping has been observed in undoped sample. The ac impedance study shows the grain boundary contribution to be predominating over the grain contribution. (C) 2015 Elsevier Ltd. All rights reserved.