NOVELTY - Improving rifamycin SV fermentation yield comprises fermenting and culturing the culture solution configured according to seed and fermentating culture medium, moist heat sterilizing, adding seed liquid of Amycolatopsis mediterranei in a first grade seed tank, controlling first grade seed tank temperature and sterile air flow rate, culturing the sterile operation into a second grade seed tank and then into a third grade seed tank, and feeding alanine, soybean oil and fosfomycin sodium or alanine, soybean oil and fosfomycin tromethamine into third-stage fermentation tank.    USE - The method is useful for improving rifamycin SV fermentation yield.    ADVANTAGE - The simple method is capable of improving the rifamycin SV fermentation yield with less energy consumption in an environmentally friendly manner.    DETAILED DESCRIPTION - Improving rifamycin SV fermentation yield comprises (1) fermenting and culturing the culture solution configured according to seed and fermentating culture medium, moist heat sterilizing after reducing the temperature to 28 degrees C, adding seed liquid of Amycolatopsis mediterranei in a first grade seed tank according to 3-5% of inoculum size, controlling first grade seed tank temperature to 28 degrees C, controlling sterile air flow rate to 0.8 vvm, and then stirring at a speed of 160 revolutions per minute (rpm) and controlling pressure to 0.03-0.04 MPa, culturing the sterile operation for 48 hours into a second grade seed tank, where the temperature, speed and pressure are maintained as same as the first grade seed tank, culturing the sterile operation for 48 hours into a third grade seed tank, where the temperature, speed and pressure are maintained as same as the first grade seed tank, and then culturing for 136 hours; and (2) feeding 0.3-0.8 g/l of alanine, 2-5 ml/l of soybean oil and 3-20 mg/l of fosfomycin sodium or 0.3-0.8 g/l of alanine, 2-5 ml/l of soybean oil and 3-20 mg/l of fosfomycin tromethamine into the third-stage fermentation tank and then culturing for 60-80 hours.