Abstract: Urechis unicinctus was boiled to process Urechis unicinctus soup seasoning.The changes of major nutrients and flavour components in soup seasoning during different boiling time were researched. The results showed that with the extension of boiling time,the content of soluble protein of Urechis unicinctus soup seasoning decreased firstly and increased subsequently.The content of component of molecular weight less than 1000 u and sensory score increased firstly and decreased subsequently.The content of fresh sweet free amino acid and organic acid increased and nucleotides decreased.Considering the good flavor,the optimum condition was boiling time 0.5 h.While condidering to get more soluble protein and organic acid,boiling time was at least 3 h.This seasoning had delicious taste,rich nutrition and could be used for a variety of seasoning development.