The invention relates to a method for cultivating mushrooms by utilizing ramie core. The method comprises the steps of preparation of culture medium, inoculation, development, growth of the mushrooms and harvest in stubbles, wherein the preparation of the culture medium comprises mixing, packaging and sterilization, and the components of the culture medium are 78 to 83 percent of powder of ramie core, 15 to 20 percent of wheat bran, 1 percent of gesso and 1 percent of ordinary superphosphate; the culture medium is cooled to below 30 DEG C, inoculated with the mushrooms, and cultivated for 18 to 20 days at a temperature of between 22 and 28 DEG C and relative air humidity of between 70 and 80 percent, so as to make the hypha grows in the whole package; the culture medium is continuously cultivated for 5 to 7 days at a temperature of between 12 and 18 DEG C and relative air humidity of between 80 and 90 percent, so as to grow the mushrooms; and then the mushrooms are harvested in stubbles according to the growth condition of the mushrooms. The method has the advantages that the method uses local materials, changes the waste into the treasure, and improves the production capacity by 10 to 15 percent compared with the prior art; the cost of the culture medium used for cultivating the mushrooms is about 80 and 60 percent lower than that of cotton seed hulls and corn cobs respectively; and the method also solves the problems that the ramie core is hard to return to the soil, the burning of the ramie core pollutes the environment, and so on.