In order to alter the existing state of low output and improve the quality of agriculture products, the necessary element for crops growing is compensated by applying multi-element fluid fertilizers developed from silicate rocks in the light of weak ecology in karst geo-environment and lack of micro-element in karst soil. The natural fluid fertilizer can supply mineral nutrition to plants and compensate nutrition element for calcareous soil. This multi element fluid fertilzer was used by over 100 peasant households and some agriculture research and productive departments to more than 700 mu land and over 20 types of crops, including rice, corn, hot pepper, rape, tobacco, fruit and vegetable, etc. in tens karst counties from the year 2000 to now. It's shows that crops yield rise obviously after fertilizeration, the production of 90% crops applied the fertilizer rise by more than 5%, and 70% of those increase by 10%or more. Additionally, the result shows that the quality of products are noticeably improved by applying the natural fluid fertilizer, which protein content increase by 1 % to 2%. Not only the amylopectin of rice increase by 2.7 %, but color, sweet smell, taste and form of fruits obviously get better. It is proved that this new method is an important way to raise output of agriculture products in karst region.