Abstract: To study the content variation of hydroxy safflor yellow A in Flos Carthami with temperature and time,and to predict the stable life of Flos Carthami under 20 ℃.The content of hydroxy safflor yellow A in Flos Carthami after accelerated by classical constant temperature method was determined by HPLC.The content variation of hydroxy safflor yellow A and the stable life of Flos Carthami under 20 ℃ were determined by Arrhenius theory.The stable life of Flos Carthami under 20 ℃ was determined to be 1.20 years using the content of hydroxy safflor yellow A as index.The thermostability of Flos carthami was relatively poor at high temperature,hence Flos carthami should be kept in the shade environment.

Key words: Flos carthami, hydroxy safflor yellow A, classical constant temperature method, stable life, HPLC