The object of experiment was to evaluate the feeding effects of golden needle mushroom barn by using the in vitro rumen fermentation to select the best feeding combination and further test it in the practice. Firstly, Firstly, we measured the nutrients compositions of golden needle mushroom barn and other roughages. Next, we designed six groups of mixture based on early study and applied in vitro rumen fermentation to measure pH, NH₃ and dry matter degradation to select the best group of mixture. In the end, beef cattle feeding trial was conducted to test the best group and 16 healthy Simonthal hybrid cattle with similar bodyweight and age were selected. The cows were randomly assigned to two groups, control group and experimental group, 8 cows each group. The cows in control group were fed basal TMR and the cows in experimental group were fed basal TMR designed by best group. The trial included 10 days for adaption, 80 days for formal experiment. Blood collection and bodyweight were conducted at the beginning and end of trial to evaluate the effects on bodyweight gain, blood physiological parameters and serum biochemical index. Results showed that nutrient composition of golden needle mushroom barn was similar to straw and maize yellow storage; The best mixture group was maize green storage(50%)+golden needle mushroom barn(30%)+beef grain(10%)+ Bean curd residue (10%); The best group of mixture significantly increased bodyweight gain of beef cattle (P<0.01), reduced the feed cost and had no detrimental effects on blood physiological parameters and serum biochemical index. To sum up, golden needle mushroom barn can be used as roughage for beef cattles.