The giant magnetostrictive Tb-Fe films assembled by nanoparticles have been prepared by the low energy cluster beam deposition. The dependence of the magnetostriction on the size of the nanoparticles is examined for the films. It is shown that the nanofilms have obtained higher saturation magnetostriction at the cluster size of 30 nm in average. The dependence of magnetostriction on particle size is ascribed to the degree of magnetic anisotropy which is related to the effective distance of exchange coupling between the adjacent Tb-Fe nanoparticles. This work demonstrates that the magnetostriction can be varied by tuning the particle size, which is important for control over the magnetostrictive properties of the films at nanoscale. (C) 2009 Elsevier By. All rights reserved.