Abstract:ACE inhibitory peptides was obtained by solid-state fermentation of soybean meal with Aspergillus oryzae.The effects of single factors including fermentation time，fermentation temperature，inoculation quantity and water content were studied with peptide yield and ACE inhibition ratio as evaluation indexs，and fermentation time were determined to be 60 h.Based on single factor experiments the fermentation condition was optimized by response surface methodology with ACE inhibition rate as index.The result showed that the optimum fermentation condition was temperature 30℃，inoculation quantity 7%and water content 56%.Under these conditions，the ACE inhibition ratio reached to 56.03%.