The stability of human blood high d. lipoprotein (HDL) injection was explored to confirm the expiration date of products. According to the theory of chem. kinetics, through the light stability test, high temperature test and accelerated test, the content and degradation rate of apolipoprotein AI (ApoAI) in injection was detected by circle immunizing method and constant temperature technique, and the expiration date of injection was calculated by Anhenius formula. The results showed that this product was stable to light but had no tolerance to high temperature The changes of ApoAI content conformed with the first order kinetics formula. The expiration date of this injection could reach 6.3 yr under the conservation below 8°C.