Abstract: 33 chemical ingredients of the essential oil of fruit of Alpinia galanga(L.) swartz have been identified and estimated by [GC]²and [GC]²/MS.The results of flash-vaporization-gas chromatography and conventional steam distillation-GC have been compared. The former method possesses such advantages as:rapidity, simplicity in manipulation and micro quantity of herb sample(about 5 mg) used. Acomponent was isolated from the essential oil by preparative TLCand identified by means of IR, ¹H-NMR and MS as 1'-acetoxy-chavicol-acetate, of which the fragmentation of mass spectra was studied through high resolution mass spectrometry and B/Elinking scanning technique. Its hydrolytic product has been isolated and identified