Abstract:The aerial parts of Codonopsis bulleyana Forrest was rich in protein， flavonoids and polysaccharide. The amino acid nitrogen was 0.820 g/100 g， flavonoids was 7.980 mg/g， polysaccharide was 0.024 mg/g. The optimum condition of enzyme hydrolysis for aerial part of Codonopsis bulleyana Forrest had been studied， amino acid nitrogen was used to as evaluation indexes. The content changes of flavonoids and polysaccharides have been investigated. The results showed that the optimum conditions of enzyme hydrolysis were obtained as follows： the papain （≥800 U/mg） content 1.4 g/100 mL， hydrolysis time 8 h， pH7.5， temperature 60 ℃， and after hydrolysis， the amino acid nitrogen content was 1.271 g/100 g， total flavonoids was 3.832 mg/g， polysaccharide was 0.040 mg/g.But the bromelain （300 U/mg） content ≥5.6 g/100 mL， hydrolysis time 5 h， pH7.5， temperature 45 ℃ ，and after hydrolysis， the amino acid nitrogen content was 5.043 g/100 g， total flavonoids was 4.484 mg/g， polysaccharide was 0.036 mg/g.In addition， The results showed that the papain higher than the bromelain on the hydrolysis efficiency.