Machining flutter is a complex and harmful vibration between the cutting tool and the workpiece in cutting processes. The mechanism of regenerative flutter theory was analyzed, the dynamics model of the Giant Magnetostrictive Actuator (GMA) flutter suppression system was established, and the stability of the Giant Magnetostrictive Actuator flutter suppression system was discussed. At last, the feasibility of the flutter suppression system based on the GMA was verified by comparing the vibration signal data of the cutting flutter experiment result with the flutter suppression experiment result.