Strontium hexaferrite SrZr x Mn x Fe 12−2x O 19 (x=0.0–0.8) nanoparticles were synthesized by chemical co-precipitation and sol–gel combustion methods. The co-precipitation is found to be more suitable because samples synthesized by this method have a single phase for x=0.0–0.8 and DC resistivity is also improved by this method, whereas samples synthesized by the sol–gel combustion method have single phase only when x=0.0–0.4. The dielectric constant and dielectric loss factor are in excellent agreement with DC electrical resistivity data.