Co and Si were selected as substitutes to improve performance of TbDyFe giant magnetostrictive alloys for special purpose, respectively. The results showed that the Co-doped Tb0.36Dy0.64Fe2 alloys can possess giant magnetostriction over a wide temperature range from -80 to 100 . Optimum magnetostriction, high electrical resistivity and improved corrosion resistance was obtained in Tb0.3Dy0.7(Fe1-xSix)1.95 system. High performance grain-aligned rods with <110> preferred orientation have been successfully prepared by zone melting unidirectional solidification. This paper also presents the design and fabrication of Giant Magnetostrictive Actuator (GMA) for active vibration control with oriented TbDyFe rods. Experimental results showed that the GMA possesses good static and dynamic performance. Excellent damping effect, 20-30 dB under the frequency range from 10 Hz to 120 Hz was obtained.