Silicon substituted lithium ferrite of different compositions (Li 0.5(1+ x) Si x Fe 2.5−1.5 x O 4) were prepared for x = 0–0.6 by ceramic standard technique. The magnetic and electrical properties of synthesized samples have been determined. A structural characterization of all the samples was conducted by the X-ray diffraction technique. The grain size ranging from 5.5 to 16 μm were studied with respect to compositions by SEM pictures. The maximum value 75.23 emu/g of saturation magnetization of silicon substituted lithium ferrite at x = 0.4 molar concentration of silicon was observed. The measured real part of dielectric constant ( ɛ′) and loss tangent (tan δ) of mixed Li–Si ferrite decreases with increasing silicon concentration in ferrite. Such variations in dielectric properties are due of Fe 2+ and Fe 3+ concentrations on octahedral sites and electronic hopping frequency between Fe 2+ and Fe 3+ ions.