In this research, a series of LaFe1-xMgxO3 (x = 0.0, 0.1, 0.2 and 0.3) perovskite material was effectively prepared using the sol-gel method followed by the sintering process. The structure property was identified by X-ray Diffraction (XRD) and X-ray Fluorescence (XRF). All compounds are single-phase without the impurity phase. XRD analysis revealed that all samples have an orthorhombic crystal structure and Pnma space group. XRF analysis showed the atomic composition for each sample which is a little bit similar to a chemical formula of LaFe1-xMgxO3, respectively. Electrical properties were characterized by RLC meter. Dielectric properties as a function of frequency (100 Hz-1 MHz) of LaFe1-xMgxO3 (x = 0.0, 0.1, 0.2 and 0.3) investigated at room temperature. The Nyquist plot showed the decrement of semi- circle diameter with the increasing of Mg content. Impedance data showed the decrease of impedance values with the increasing of Mg content. Based on dielectric studies, the dielectric spectra showed the decrease of loss dielectric as Mg doping increases. Room temperature dielectric constant (ϵ′) of samples increases at a lower frequency with the increasing of Mg-doped.