Abstract: To study the changes of free amino acids in chicken during cooking, seventeen kinds of free amino acid ( FAA) content in chicken specimens and broth under different time in 95℃ were examined through reversed phrase high- performance liquid chromatography ( RP- HPLC) with pre- column derivation method.The results showed that: Proteins degraded in varying degrees under different time in 95℃.For the different rates of formation and degradation and the different amounts of FAAs effused into broth, the contents of FAAs in surface specimens displayed increase and then decrease, while reaching the maximum at 40 minutes; and that in central specimens showed a gradual increase, while reaching the maximum at 120 minutes.A sharp rise was observed in soup samples, for that meat samples' FAA dissolved in it, the FAAs content of 120min was about five times as that of 10min.So within two hours heating, the chicken soup would be more delicious and nutritious with the extension of time.