NOVELTY - Producing water-soluble fertilizer containing humic acid, involves precipitating waste liquid of yeast by settling pond, evaporating and condensing the waste liquid of yeast, mixing the condensed waste liquid with the waste liquid of original yeast, fermenting the mixture naturally, arranging the naturally fermented waste liquid in a warming and stirring tank, stirring the mixture uniformly, heating the mixture, adding monopotassium phosphate to the mixture, adding mineral humic acid to the mixture, adding urea to the warming and stirring tank, and filtering the product.    USE - The method is useful for producing water-soluble fertilizer.    ADVANTAGE - The fertilizer consumes less energy, overcomes problems of large amount of bioactive Saccharomyces inactivation, and contains humic acid and soluble elements, hence it increases yield of crops, quality of agricultural products and soil fertility.    DETAILED DESCRIPTION - Method of producing water-soluble fertilizer containing humic acid, involves (a) precipitating the waste liquid of yeast by settling pond, where the waste liquid is produced by yeast plant, and evaporating and condensing the waste liquid, (b) mixing the condensed waste liquid with the waste liquid of original yeast, and fermenting the mixture naturally, (c) arranging the naturally fermented waste liquid in a warming and stirring tank, stirring the mixture uniformly, heating the mixture at 45-50 degrees C, and adding monopotassium phosphate to the mixture until the monopotassium phosphate is dissolved completely in the mixture, where the monopotassium phosphate is 8-10% of the quality of water-soluble fertilizer, (d) adding mineral humic acid (8-9% of the quality of water-soluble fertilizer) to the mixture at 45-50 degrees C until the humic acid is dissolved completely in the mixture, (e) adding urea (20-22% of the quality of water-soluble fertilizer) to the warming and stirring tank at 45-50 degrees C until the urea is dissolved completely, and (f) filtering the product to obtain supernatant liquor to obtain the water-soluble fertilizer containing humic acid.