Star-shaped polystyrenes with the [60]fullerene core were synthesised via anionic polymerization. The solution, thermal, and UV absorbance properties were investigated as a function of number of branched polystyrene chains on the [60]fullerene core. The solution viscosity (intrinsic viscosity) of the [60]fullerene-modified polystyrene decreased with the number of branching due to molecular entanglement. The better coating property of the [60]fullerene-modified polystyrene compared with those of the polystyrene/[60]fullerene mixtures seems to arise from a lower aggregation state of the [60]fullerene core induced by the branched polystyrene chain. An increase in the glass transition temperature of the modified polystyrene with the number of branched chains was observed as well.