To provide a gas-liquid reaction method and apparatus which can improve ozone use efficiency from a standpoint of equipment engineering paying attention to a flow behavior of ozone microbubbles in an air-lift type gas-liquid reaction apparatus by installing a particular draft tube or partition plate in the apparatus.

In the gas-liquid reaction method and apparatus, a microbubble generator is incorporated in an air-lift bubble column, a ratio of the cross section of a downflow portion to the column is controlled by a diameter of the draft tube and a position of the partition plate to control the flow behavior of the microbubbles in the column.