The purpose of this study was to develop Ti–Au alloys with a higher resistant to corrosion, better biocompatibility, and better mechanical properties than the commercially pure titanium and its alloys. Ti–Au alloys were designed with a gold content that ranged from 0 to 5.0 at % in steps of 1.0 at %. Properties of the alloys including chemical composition, microstructure, phase, hardness, electrochemical properties, and the cytotoxicity were investigated. Only the α phase existed in the Ti–Au alloys. The addition of gold to the titanium decreased the α to β transformation temperature. The acicular α phase became thinner and the hardness value increased with increasing gold content. In the electrochemical tests, Ti–Au alloys had a higher resistant to corrosion than had pure titanium and did not exhibit pitting corrosion in artificial saliva. The cytotoxicities of the Ti–Au alloys were similar to that of pure titanium. Therefore, Ti–Au alloys could be used as biomaterials in the medical and dental fields.