Mg ferrites with magnetic and dielectric properties are widely used composites to stabilize spinel structure. This study investigates the effect of sintering temperature (900°C, 915°C, 930°C, 945°C, 960°C) on the magnetic and dielectric properties and low-loss characteristics of Mg0.7Cd0.3Fe1.92Ga0.08O4 composites with 5 wt.% Bi2O3 addictive. The change in temperature enhances magnetization (saturation magnetization Ms from 24.37 emu/g to 33.12 emu/g), hence increasing permeability. The real permeability (μ’) of Mg-Cd-Ga ferrites was examined to be monotonically increasing from 15 H/m to 19 H/m. And the real part of permittivity (ε’) was fine-tuned by increasing temperature. As a result, at 920°C,μ’ and ε’ are closely equivalent ranging from 1 MHz to, this characteristics can be used for miniaturization and good radiation behaviors antennas. In addition, very low magnetic (tanδμ
~3*10−2) and dielectric (tanδε
~5*10−3) tangent enable excellent radiation efficiency at operation.