This study performs molecular dynamics (MD) simulations to investigate the structural features and diffusion properties of fullerene-in-water suspensions. The numerical results reveal that an organized structure of liquid water is formed close to the surface of the fullerene molecule, thereby changing the solid/liquid interfacial structure. The organized structure formation becomes more pronounced as the fullerene size is reduced. This observation implies that a transition zone exists between the organized liquid water layers and the random distribution region. Furthermore, the results indicate that the structural stability of fullerene-in-water suspensions improves as the fullerene volume fraction increases, but is insensitive to changes in the fullerene size. Finally, the simulation results reveal that the diffusion coefficient of the water molecules varies as a linear function of the fullerene loading, but is independent of the fullerene size.