Abstract:Thin-layer chromatography and a dual wavelength TLC-scanner (shimadzu CS-930)were used for qualitative analysis of differently processed Lonicera japonica Thunb. (air-dry, stoving, nitric gas fumigating), and for the determinatioa of contents of the active chlorogenic acid. The results shows that both the content and the quality of the drug by different processing are basically the same. Nitric gas fumigating can thus be used for increasing the quality of appearance of the drug Lonicera japonica Thunb.