The electrical properties of Ni_0.27Cu_0.10Zn_0.63Fe₂O₄ (NCZF) prepared from auto combustion synthesis of ferrite powders have been studied by impedance and modulus spectroscopy. We studied frequency and temperature dependencies of impedance and electric modulus of NCZF in a wide frequency range (20 Hz–5 MHz) at different measuring temperatures $T_{\text{SM}}$ (30–225 ℃). The complex impedance spectra clearly showed both grain and grain boundary effects on the electrical properties. The observed impedance spectra indicated that the magnitude of grain boundary resistance $R_{\text{gb}}$ becomes more prominent compared to grain resistance $R_{\text{b}}$ at room temperature, and with the increase in $T_{\text{SM}}$, $R_{\text{gb}}$ decreases faster than the intrinsic $R_{\text{b}}$. The frequency response of the imaginary part of impedance showed relaxation behavior at every $T_{\text{SM}}$, and the relaxation frequency variation with $T_{\text{SM}}$ appeared to be of Arrhenius nature and the activation energy has been estimated to be 0.37 eV. A complex modulus spectrum was used to understand the mechanism of the electrical transport process, which indicated that a non-Debye type of conductivity relaxation characterizes this material.