The scale-up effect on the dynamic behavior of gas-liquid-solid three-phase reactors was investigated by using columns of three different diameters (200, 400 and 800 mm). The local and time-dependent behavior of bubble and particle motions in three-phase reactors were characterized in terms of the correlation dimension obtained by the deterministic chaos analysis for the series of the time intervals between successive bubbles or particles by means of the embedding method. With regard to the dynamic behavior of pas phase, the large-scale column was found to have a relatively small correlation dimension because of the coherent gross circulation flow structure induced by the bias in the bubble formation on the distributor. No significant column size effect on the chaotic dynamics of solid particles was observed.