The invention relates to a method for preparing high-yield Tremella polysaccharide by taking a culture medium for fermenting and belongs to the technical field of microbial fermentation culture. The method comprises the following steps of: based on Tremellafuciformis CGMCCC (China General Microbiological Culture Collection Center) 5.466 as a strain, firstly, inoculating the strains into a seed culture medium to culture for one day; inoculating cultured seeds into a fermentation culture medium to culture, wherein the fermentation liquid loading amount is 5L, and the fermentation period is 72 hours; centrifuging fermentation broth, collecting, concentrating, carrying out alcohol precipitation and diethyl ether washing, and drying to obtain 9.5g/L high-yield Tremella polysaccharide. By using the method, the fermentation period is effectively shortened; and the method has the characteristics that process is simple and easy to operate, environment pollution is little, high-yield polysaccharide can be obtained, and industrialization is easy to realize.