The orthogonal design approach is adopted to perform the cutting force experiment. It is based on the three typical metallographic phases of TC4 titanium alloy. The multiple-variable linear regression equations of the cutting force are built in term of the main technical parameters using the MINITAB software. Regression analysis is done, and an accurate empirical formula of TC4 cutting force is established. It is also optimized the cutting process parameters. The heat treatment’s technical laws of cutting force of TC4 titanium alloy are further undertaken, which provide a theoretical basis for improving cutting performance and optimizing turning parameter.