The movement of nanosized Au clusters on Si bicrystal was found to be critically influenced by strained fields of the buried twist-dislocation network by in situ ultrahigh vacuum transmission electronic microscopy. Collective movement of Au atoms was observed. Most strikingly, clusters of more than three million atoms move concertedly by one dislocation spacing (7-45 nm) within 130 s at a substrate temperature of 250 °C. The "jumping" mechanism is attributed to the viscous flow. The observation shall serve as a good reference to refine the theory to realize the control of self-organized nanoparticles on silicon bicrystals.