Photoinduced Clustering of polystyrene microbeads and photocentra oftheir diffusion was achieved, in water with the assistance of.photoinduced transformation of supramolecular architecture of amphiphilic diarylethene between sphere, and fiber states. When a suspension of polystyrene beads containing the sphere state of diarylethene was UV-irradiated from berieath, clustering, of the. polystyrene beads by thermal convection was observed. The velocity of clustering was dependent on the amount of photogenerated nanofibers that determines the viscosity of the water.. Diffusion of the - clustered polymer: beads was: supitressed by the, surrounding fibers, but was: restored to regular Brownian motion., upon:- irradiation with visible light. It was suggested that the diffnsion of transformation of aggregates between the more viscous fiber state and the less viscous insight into the photocontrol of particle motion in fluidic media. the microbeads was controlled by the Sphere state. These results provide new insight into the photocontrol of particle motion in fluidic media.