The invention relates to a titanium alloy component quantifying design method, which comprises the following steps: proceeding from the practical phase change process of the titanium alloy and establishing a mathematical model of a strengthening weight and a strengthening factor of the titanium alloy under different heat treatment conditions on the electronic structure level, then taking a tensile strength and a tensile stretch value of alpha-Ti and beta-Ti as basic values, and utilizing the strengthening weight and the strengthening factor to calculate a strength increment and a reduction of the tensile stretch under different heat treatment conditions so as to calculate values of the tensile strength and the tensile stretch of the titanium alloy under different heat treatment conditions; and programming a calculation formula into a calculation software, observing the variation quantities of the tensile stretch and the tensile stretch of alloying elements under different heat treatment conditions on the computer, and repeatedly adjusting the chemical components of the alloy to make relative errors of theoretical calculated values and technical requirement values of the tensile strength and the tensile stretch of the designed alloy in the range of 10 percent so as to determine the components of the titanium alloy. The invention has rapid and economy design process and high accuracy of the design result, and provides the reference value for the component design of other alloy systems.