The quality of threaded connections has a great impact on the reliability, precision and precision stability of the product. At present, the tension of miniature fastener in precision instruments can not be measured and controlled quantitatively. Therefore, a tension measurement and control method for miniature screws is proposed, and the tightening process of miniature screws is studied. Taking M2 screws as experimental objects, the influence of tightening times on nut factor and the degree of dispersion of nut factor of titanium alloy M2 screw are studied. The tightening process is analyzed, and the technological method to improve the tension control accuracy of the Torque Method is discussed.