Summary: To establish the determination method of dauricine (Dan) concentration in rats’ blood and other biological samples, a reverse-phase HPLC method was adopted. Under the given condition, dauricine could be well separated. The retention time (tR) of Dan and its internal standard, daurisoline were 9. 2 and 6.1 respectively. The detection limit was 10-2 mg/ml. The absolute recoveries of all kinds of samples were above 70 %, and the relative ones were over 85%. A good liner relationship has been obtained over the entire range of 0. 030 to 3. 000 rug/L in blood samples and 0. 050 to 5. 000 mg/L in other tissue samples. The intraday and interday coefficients of varia- tion were below 10 %. The results showed that the method can be used for detecting Dan in all kinds of biological samples.