Abstract: AIM: To investigate the effective parts of Radix Aster and synergistic effects of Flos Farfarae by eliminating phlegm experiment.METHODS: Radix Aster, Flos Farfarae extractionmethods were established as 30 % ethanol backstreaming extraction and water extraction, respectively, indexed with phenol red excretion.The extractive was precipitated using alcohol and 3 parts were extracted :60 % ethanol parts, 90 % ethanol parts, and 90 % ethanol solution parts.RESULTS: The effective fraction of Radix Asteris was 90 % ethanol parts (RA2), the synergistic fraction of Flos Farfarae was 90 %ethanol solution parts (FF3). CONCLUSION: The effective fraction of Radix Asteris is in high polar region, the synergistic fraction of Flos Farfarae is in low polar region.

Key words: Radix Asteris, Flos Farfarae, effective parts, eliminating phlegm, compatibility parts