Abstract: Two forms of santonin exist in Artemisia cina Berg, i. e, α-and β-santonin. α-Santonin is therapeutically effective as an anthelmintic, while β-santonin is very weakly effective, so a method for the separation and determination of both forms is required. In the present paper, separation is made on silica gel-aluminum oxide G layer and determination is performed with a Shimadzu Chromatogram Scanner Model CS-900.Weigh accurately 0.20g of Artemisia powder (60 mesh) into a 50 ml Erlenmeyer flask, add 0.10g of Ca(OH)₂ and 10.0 ml of water, then weigh the flask accurately. Boil the mixture for 10 minutes, cool, and weigh again, add more water to compensate the weight loss on boiling. Filter, apply the filtrate onto a silica gel-aluminum oxide G layer, develop with ethanol-conc, ammonia water (8:0.3), (R_f value: α-santonin 0.45,β-santonin 0.55). Scan the spot area of α-and β-santonin with a Shimadzu Chromatogram Scanner, Model CS-900, and calculate the weight with a calibration curve. Construct caliberation curves by plotting micrograms of standard α-and β-santonin vs. spot areas, two straight lines are obtained between 1～3μg, Instrument parameters are λ_s 270 nm, λ_R 400 nm, slit 10 mm, sensitivity x l, scan speed 40 mm/min, method of scanning: reflectance.The method is simple and rapid and is more sensitive than the elution method. The recovery of α-santonin is 95%. The method has been applied to the analysis of a number of different Artemisia samples.