Abstract: In the summers of 1998 and 1999, Chinese and Japanese scientists cooperatively conducted the first large-scale energy and water cycle experiment in the Huaihe River Basin, Anhui province of China (WCRP/GEWEX/GAME/HUBEX). The major objective of this field experiment (HUBEX) was to investigate the multiple-scale structure characteristics, the life cycles, the genesis and development mechanisms of the Meiyu system in East Asia as well as the cause of related flooding disasters. It was a joint China-Japan cooperative meteorological and hydrological observation experiment. On this basis of the intensive observations, the two partners continued to conduct a follow-up research for another five years to collate and compile data, and perform analysis and scientific research. It can be concluded that the HUBEX project had yielded comprehensive and remarkable achievements. This paper introduces the major scientific results derived from this project and reassesses their merits and shortages for the purpose to provide useful experiences and propose new research targets as well as prospects for the initiation of a new joint scientific Meiyu experiment in the middle and lower Yangtze River Basin.