Abstract: Several plant drugs, including Stephania tetrandra S. Moore (roots), Fritillaria thunbergii Miq. (bulbs), Leonurus heterophyllus Sweet (herb), Stemona tuberosa Lout. (roots), Sophora flavescens Air. (roots), Lycoris radiata Herb (bulbs) and Abrus contoniensis Hance (herb) have been studied for their analytical methods, in order to find some general rules for the determination of the alkaloid content of plant drugs. The analytical method of alkaloidal plant drugs consisted of three operations, i.e., extraction, purification and determination. The three operations were studied for each drug as follows: 1. Extraction with different solvents and in different ways (maceration, percolation and reflux). 2. Purification of the alkaloid extract by alumina adsorption column, by extraction in separatory funnel, or with no purification at all. 3. Titration with standard acid or silicotungstic acid solution. From these results, the analytical procedure for each drug was worked out.