The invention belongs to the field of denture production, and particularly relates to a dental titanium alloy and a preparation method thereof. The dental titanium alloy is characterized by comprising35-45 parts of pure titanium and 55-65 parts of a titanium alloy, wherein the pure titanium comprises the following elements in mass fraction: smaller than or equal to 0.3% of Fe, smaller than or equal to 0.1% of C, smaller than or equal to 0.05% of N, smaller than or equal to 0.015% of H, smaller than or equal to 0.25% of O, smaller than or equal to 0.4% of other impurities and the balance of Ti; the titanium alloy comprises the following elements in mass fraction: greater than or equal to 5.5% and smaller than or equal to 6.75% of Al, greater than or equal to 3.5% and smaller than or equalto 4.5% of V, smaller than or equal to 0.3% of Fe, smaller than or equal to 0.08% of C, smaller than or equal to 0.05% of N, smaller than or equal to 0.015% of H, smaller than or equal to 0.2% of O, smaller than or equal to 0.4% of other impurities and the balance of Ti. A pure titanium material is used at the top end of the alloy material, and the alloy material has low mechanical strength, is used for producing the cutting end and the occlusal surface of a denture, is in contact with an opposite jaw and has less wear on a natural tooth; the middle part and the bottom of the titanium alloy have relatively great strength; as a main structure of the denture, the titanium alloy has good mechanical properties, can bear a relatively large occlusal force, and is good in biocompatibility.