The volatile compounds in soybean meal before and after fermentation with four different dry yeasts were analyzed by HS-SPME. The results showed that 36 volatile compounds in soybean meal were identified, and the major components were 1-octen-3-ol, 1-hexanol, ester and aldehyde. The content of 1-octen-3-ol was the highest, which accounted for 34.03%. After fermentation with Angel yeast, Mauri yeast, Sugarman yeast and Chaofan yeast, 54, 51, 57 and 52 volatile compounds were identified in the fermented soybe...