The electrical resistivity of pure Al, pure Sn, pure Mg and the compounds with the general composition [96.5-x] at. % Al-[x] at. % Sn-3.5 at. % Mg (x = 2.5 (supra-eutectic), 8.5 (eutectic), 14.5 (sub-eutectic)) were measured by four-point probe (DC 4PPT) method in the temperature range of 323-823 K. The electrical resistivity of the alloy was observed to increase depending on the temperature. The temperature coefficients for the compounds with the general composition [ 96.5-x] at. % Al-[x] at. % Sn-3.5 at. % Mg (x = 2.5, 8.5, and 14.5) are 82.16 x 10(-4), 11.72 x 10(-4), and 4.53 x 10(-4) respectively. The variations of thermal conductivity were determined by Wiedemann-Franz Law (W-F) and Smith-Palmer (S-P) equation using the data obtained from electrical properties. Thermal conductivity values for the three compounds of alloy were decreased depending on the temperature. The microstructures of the same ternary alloys were obtained from SEM (Scanning electron microscopy), MAPPING and EDX (Energy Dispersive X-ray Spectroscopy) analysis. (C) 2020 Published by Elsevier B.V.