[en] Soft Ni-Mg spinel ferrites having general chemical formula Ni_1-xMg_xFe₂O₄ (0 ≤ x ≤ 1) with increment 0.25 were prepared by the co-precipitation method. The samples were characterized by X-ray diffraction (XRD) technique at room temperature. The analysis of XRD data showed the crystallite size variation within the range 10-13 nm. The electrical and magnetic properties of the synthesized ferrites have been investigated as a function of temperature. The DC electrical resistivity (ρ) decreases with increase in temperature exhibiting the semiconductor like behavior. The drift mobility (μ_d) and activation energy (ΔE) are also reported. The dielectrical properties such as dielectric constant (ε') and dielectric loss tangent (tan δ) are investigated as a function of frequency. The Curie temperature (T_c) of the present work was determined from AC magnetic susceptibility (χ) data and observed variation are explained on cations distribution among tetrahedral (A) and octahedral (B) sites.