In order to avoid result that cam follower could be vibrate on the condition bad stiffness or higher speed using routine cam motion law,the method of harmony synthesis is used. The motion output function is optimized with aim function which is ideal motion demands. Through the natural frequency of cam and angular frequency,the number of harmonic wave terms is determined. The coefficient of equation is solved. Taking the global indexing cam in the folding turret of YB49 as an esample,the design is carried out,the design result is compared with the previous cam in FC800,the value of maximum accelerated velocity and maximum velocity are declined. Comparing with the cam in the FOKCE701,the number of harmonic wave on the static state is same. So the method could be applied to the other high- speed cam.