The Ti-6Al-4V Extra Low Interstitial (ELI) alloy has been widely recognized as a bone and dental implant material due to its excellent biocompatibility properties. In this research, to fabricate the Ti-6Al-4V ELI alloy, a melting and alloying process has been carried out using a single arc melting furnace flowing with argon gas. The alloyed cast sample was given a heat treatment process with solution treatment at a temperature of 950°C for 30 minutes followed by rapid cooling in water, and then aging, which was carried out at temperature variables of 400, 500, 600, and 700°C with furnace cooling. Microstructure observation was carried out with an optical microscope and a hardness test was performed using the Vickers hardness method. The results of microstructure observation showed that it changed after the aging process. The results of XRD analysis showed that the intensity of the β phase at temperatures of 400, 500, 600, and 700°C are 15.4, 27.35, 29.3, and 32.46%, respectively, with the intensity of the α/α' phase of 84.6, 72.65, 70.7, and 67.5%. The highest hardness was obtained in the aging variation at the temperature of 600°C, which was 563 HVN, while the highest corrosion resistance of 0.016 mmpy was found in the aging variation at the temperature of 700°C. [ABSTRACT FROM AUTHOR]