<p>This work investigated the corrosion behavior and cathodic protection using cast zinc sacrificial anode of different welded zones of a steel plate used in overhead tanks. The steel plate was characterized using XRF and was welded using electric arc welding. The various welding zones were obtained, and the microstructure was recorded using optical microscopy. In addition, the welded zones were subjected to corrosion tests using potentiodynamic polarization. Another welded steel plate was coupled with a cast zinc sacrificial anode immersed in water for four weeks, and the anode efficiency after every week was recorded. Also, SEM/EDS of the sacrificial anode was recorded. From the results, the fusion zone shows grain enlargement compared to the heat-affected zone and the base metal. In addition, the fusion zone shows less corrosion resistance than the other zones. Finally, the cast zinc sacrificial anode shows an efficiency of 95.42%, which decreases to 54.52% after the fourth week. Therefore, zones of welded steel plate used in overhead tanks have different corrosion properties and can set a galvanic cell in the welded plate, which can cause failure. Cast zinc sacrificial anode can protect the welded steel plate used for overhead tanks.</p>