The radix Daphne genkwa was sequentially extracted by petrol ether, chloroform, acetyl acetate, acetone and ethanol and
the chemical
constituents of the extracts (E 1 ~E 5 ) were analyzed by GC MS. The inhibition on acute inflammation of the extracts was evaluated by the enhancement to phagocytic activity of reticular epithelial system (RES) to Congo red and the inhibition on vascular permeability in mice. 93 compounds including 75 aliphatics, 13 aromatics (predominately comprised by acyl phthalate derivatives) and 5 alkaloids were identified in E 1 ~E 5 , among which the total content of aromatic compounds in E 5 was observed to be 24.943%, much higher than those in E 1 ~E 4 . On inhibition of acute inflammation, the 5 fractions presented obvious enhancement on phagocytic activity of RES and inhibition of vascular permeability. E 5 , with the highest content of aromatic constituents, indicated stronger action for inhibiting acute inflammation. The existence of acyl phthalate derivatives might be the reason for radix Daphne genkwa to possess inhibition on acute inflammation. This inhibition is likely to be realized by enhancing phagocytic activity of RES and competitively binding with histamine receptor.