Abstract: Gas-liquid two-phase flow is one of the most commonly occurring types of flow. Several research areas such as the mechanistic studies, parameter measurements and industrial applications of the two-phase flow are strongly influenced by the flow regime. Therefore it is of great importance that the research of flow regimes and particularefforts have been given to methods of flow pattern recognition. Studies on the gas-liquid two-phase flow regime in recent years have been reviewed in this article. The definition and classification of each flow regime, the flow regime map, flow pattern transition criteria and the methodology of flow regime recognition were focused.