Lithium-zirconium-cobalt ferrites bearing the chemical formula Li0.5ZrxCoxFe2.5-2xO4 for x ranging from 0.0 to 0.5 with the step increment of 0.1 were synthesized by the sol-gel auto combustion technique. The variation of Zr-Co substitution has a significant effect on the structural, electrical and magnetic properties of lithium ferrite. Lattice parameters 'a' increased from 8.331 to 8.358 A. Cation distribution data suggest that Co2+ and Li+ show marked preference for octahedral B-site, whereas Zr4+ and Fe3+ occupy both the available sites. The IR spectra show two major absorption bands related to the spinet structure of ferrite. Saturation magnetization decreased whereas coercivity increased with the increase in Zr-Co substitution. Resistivity and activation energy increased whereas dielectric constant decreased with the increase in Zr-Co substitution. Dielectric constant increased with the increase in temperature from 403 to 773 K at a constant frequency of 1 kHz. The possible reasons responsible for the changes in structural, electrical and magnetic properties with the increase in Zr- Co substitution are undertaken. (C) 2012 Elsevier B.V. All rights reserved.