The invention discloses a gibberellin-containing hydroponic leaf vegetable organic nutrient solution and a preparation method of the nutrient solution. The nutrient solution comprises the following material components in percentage by weight: 20 percent of sword beans, 20 percent of rice bran, 20 percent of water hyacinth, 10 percent of bone meal, 10 percent of potato vines, 10 percent of cucumber stems and 10 percent of tomato leaves and consists of fermentative microflora I and fermentative microflora II. The preparation method is characterized by comprising the following steps: preparing biological gibberellin from tender pods of sword beans by utilizing a fermentation process, matching with nitrogen, phosphorus and potassium and other trace elements in the main materials, fermenting to form the nutrient solution needed by leaf vegetables, fermenting by virtue of the fermentative microflora, thereby obtaining an active enzyme. A gibberellin growth regulator gibberellic acid (GA3) contained in the nutrient solution disclosed by the invention belongs to an active substance enzyme, effective absorption of plants on the active gibberella is improved, the yield of the cultivation target is increased, the nutritional requirement on full growth of the leaf vegetables can be met by virtue of a nutrition formula, the development of the root system and leaf surface is promoted, and the piece weight and quality of finished plants are increased.