Based on the design principle of alternating current electromagnetic circuit, this paper presents the design of a novel low-frequency high-power miniaturisation of the giant magnetostrictive actuator (GMA) under 10 kHz using Terfenol-D rod. A smart composite material is developed for noise reduction in underwater target. Finite element method is adopted to simulate and optimise the design of smart material structure, and the simulated resonance frequencies of the giant magnetostrictive materials (GMM) are found to be consistent with the measured values. Experiments were carried out in the water tube with GMM as active acoustic absorption material in active acoustic control system. Research results show that the giant magnetostrictive composite smart materials are active sound absorption materials effective for light-weight low-frequency broadband.