Humic acid(HA)has been applied to agricultural production for its many advantages.HA,the traditional organic fertilizer,has been used in the hydroponic vegetable cropping with the development of HA and inorganicorganic nutrient solution research in recent years.In this paper,the production mechanism and character of HA was introduced,and researches of HA in hydroponic vegetable cropping was summarized.The application prospect and scientific problems in HA further research in the hydroponic vegetable field were also outlined.