The invention belongs to the biomedicine technical field, concretely relates to a method for purifying rapamycin from broth. In order to raise the purity of rapamycin, reduce the impurity content in rapamycin and increase the yield of rapamycin, the invention uses mycelium extraction, broth extraction, macroporous resin adsorption, silicagel column chromatography, cooling crystallization and recrystallization to extract and purify the rapamycin pure product from the broth, the purity is greater than 99.3%, the single impurity is less than 0.10% and the yield is increased to 53-60%. According to the invention, the rapamycin purity is raised, the impurity content is reduced, the yield is enhanced simultaneously, the operation is convenient, the technology is simple, and the method for purifying rapamycin from broth has high utility value in large industrial production.