This report typically discusses the Voltage-Stability (V-S) of the electrical properties of a new perovskite oxide, Ba0.97La0.02Ti1-xNb4x/5O3 (noted BLT, BLT0.9Nb0.08) ceramics which have been meticulously studied. The ceramics typically exhibited a low rise in the real and imaginary parts of the complex impedance on the application of small field levels (up to 5 V). These accurate data, at a low voltage threshold, properly designate a hole-generation process which becomes active. These values considered using AC impedance spectroscopy, nonetheless, were relatively decreased with increasing Nb concentration, as well as increased by this application of a DC bias. For each sample, the complex impedance plot displayed a single impedance semicircle, identified over the high and low frequencies. The equivalent circuit configuration was typically fitted using the Electrochemical Impedance Spectroscopy (EIS) spectra analyzer. Importantly, the electrical properties of our both compounds deduced from the complex electric modulus show a conduction process due to the short-range mobility of charge carriers. An excellent addition of Niobium to some considerable extent can inhibit the grain growth. Conspicuously, the substitution of Nb5+ ions for Ti4+ on B sites leads to the noticeable increase of a band gap. These findings supplied critical insights into the electric mechanisms in BT-based ceramics.