Ozone decomposition on the iron oxide catalyst was carried out in four types of spouted beds and the gas conversions were compared, for the purpose of comparing the gas-solid contacting efficiency of these spouted beds. These four types include a top-sealed spouted bed, a screen-bottomed spouted bed, and top-outlet spouted bed with or without a draft-tube. The top-sealed spouted bed and the screen-bottomed spouted bed provided higher gas conversion compared with the other two types of spouted beds. The gas-solid contacting efficiency of these spouted beds was compared with that of a hypothetically sothermal fixed bed. The top-outlet spouted bed with a draft-tube provided poorer contacting efficiency than the other types of spouted beds.