Mn_0.50-xZn_0.50Cu_xFe₂O₄ (where x = 0.0 - 0.3) ferrites have been synthesized by auto combustion method. X-ray diffraction patterns reveal that all compositions are of single phase cubic spinel structure. The lattice parameter decreases with the increase in Cu²⁺ content obeying the Vegard’s law. The bulk density, average grain size, initial permeability, Néel temperature and saturation magnetic induction of Mn_0.50-xZn_0.50Cu_xFe₂O₄ increased with increasing Cu²⁺content. It is observed that both density and initial permeability increase with increasing sintering temperature. The maximum initial permeability is found to be 1061 which is almost four times greater than that of the parent composition. The resonance frequency of all the samples shifts towards the lower frequency as the permeability increases with Cu²⁺ content. It is observed from B-H loops of Mn_0.50-xZn_0.50Cu_xFe₂O₄ that coercivity decreases and retentivity increases with Cu²⁺ content. Possible explanations for the observed magnetic properties with various Cu²⁺ contents are discussed.