The invention belongs to a magnetostrictive field, and relates to a nested giant magnetostrictive actuator. The nested giant magnetostrictive actuator mainly comprises a magneto-resistance base, a lower magnetic conductive plate, a coil skeleton, a magnetostrictive sleeve, a magnetic conductive sleeve, a magneto-resistance sleeve, a lower magnetic conductive block, a magnetostrictive rod, an upper magnetic conductive block, a cylindrical magnet yoke, an upper magnetic conductive plate, a magneto-resistance shell, a magneto-resistance ladder transmission shaft, a pre-tightening cover and a disc spring. The nested giant magnetostrictive actuator has the advantages of reasonable structure, simple operation and the like, and the output displacement of the actuator can be increased by combining magnetostrictive materials in different shapes and internal transmission structures of the actuator. The application occasions of the magnetostrictive actuator are widened, and the actuator has significance for practical application of the actuator.