<p>In our study, Zn_7-xMn_xSb₂O₁₂ (<i>x</i> = 0, 0.1, 0.2, 0.3, 0.4) ceramics with various amounts of Mn were prepared by coprecipitation method. The structural and electrical properties were analyzed by X-ray diffraction (XRD), EDS analysis, and an impedance analyzer. The XRD has confirmed the existence of the pure Zn₇Sb₂O₁₂ spinel phase in Zn_7-xMn_xSb₂O₁₂ ceramics. With an increase in the Mn content of the additive from <i>x</i> = 0 to 0.4, the peaks of Zn₇Sb₂O₁₂ considerably weaken. This fact suggests that the crystallinity may increase with the increase in Mn concentration in the host structure. The molar ratio Zn:Sb:O is about 7:2:12 and the occurrence of O²⁻, Zn²⁺, Sb³⁺, and Mn²⁺ in Zn_7-xMn_xSb₂O₁₂ have been confirmed by the EDS spectrum. As the relative density increases, the Zn_7-xMn_xSb₂O₁₂ ceramics with <i>x</i> = 0.4 exhibited the maximum leakage current density (7.2μA/cm²) and the nonlinear coefficient decreases from 16.6 (<i>x</i> = 0) to 8.7 (<i>x</i> = 0.4). The impedance spectroscopy has also been used to find samples with <i>x</i> = 0.3 exhibited the maximum grain boundary (<i>R</i>_<i>gb</i> = 19.73&#xa0;MΩ·cm) among other doped samples. The <i>E</i>_<i>a</i> value of the Zn_7-xMn_xSb₂O₁₂ ceramics is found to decrease from 1.32 eV (<i>x</i> = 0) to 1.03 eV (<i>x</i> = 0.4) due to the increase in oxygen vacancy concentration. All ceramics have a non-Debye relaxation phenomenon. These findings introduce Zn_7-xMn_xSb₂O₁₂ ceramics for new applications in varistor devices.</p>