Abstract:This paper reports the determination of strychnine and brucine in different parts of Semen Strychni (the seeds of Strychnos nux-vomica and S.pierriana), and makes a comparison of the contents between the crude forms and processed products of the two seeds. Based on the results, the authors have made some discussion about the relationship between the alkaloid distribution in Semen Stryehni and its processing.