During the process of high-efficiency cutting Ti6Al4V the material presents serrated chips. Periodic high-frequency serrated ship will cause fluctuations in the cutting force, which then affect the tool wear and surface integrity of workpiece and so on. On the basis of experiment of turning Ti6Al4V, the frequency and the geometric characteristics of serrated chip has been analyzed through observing the microstructure of chip using optical microscope and SEM. The results show that cutting speed and feed rate have great influence on the frequency and the geometric characteristics of serrated chip. Involving low-speed, large feed and large cutting depth can reduce the generated frequency of serrated chip.