Abstract: Strains breeding and optimization of submerged fermentation conditions of Changshu Yushan Tricholoma matsutake were studied in this paper. The predominant strain of Tricholoma matsutake in liquid culture was screened by testing mycelium ball diameter, mycelium ball number, mycelium dry weight of the ball and day of mycelium growth rate under different incubation time.NO.2 was used as experimental strains.Mycelium submerged fermentation culture conditions were optimized. The effect temperature, shaking speed and fermentation cycle on Tricholoma matsutake submerged fermentation were researched by single factor experiment. The optimal fermentation conditions determined by the response surface test was 25 ℃, 170 r / min and 8.5 d, under which the dry weight of mycelium was 14.5 mg / m L.