Ultrasonic deformation and even fracture of one-dimensional nanomaterials usually occur under sonication, which is likely to have a significant effect on their physical and chemical properties. However, this process and the mechanism underlain are still unknown and yet to be found out. Herein, we establish a ‘bubble-jet impact’ model to study the specific behaviour of fracture evolution of nanowires in sonication processing. By recording the plastic deformation and absorbency of certain sonicated nanowires, e.g., Ag and Cu, a strong size-dependent breakage induced by the bubble-jet is well validated, which shows that relatively long nanowires tend to fracture by bending while short or medium-length nanowires, as fractured remainders of long ones, have the inclination to be tensile broken. The transition point between the two types of fractures has also been discovered. Our results not only provide guidelines for ultrasonic dispersion, but also pioneer a possible way for controllable functional modification of one-dimensional nanomaterials.