Abstract: This paper shows the chenical constituents of the essential oil from Limnophila rugosa (Roth)Mwrr.By the aid of PGC,GC-MS and IR, the following components have been separated and identified; linalool (0.08%),estragole (21.94%),cis-anethole (0.03%),anisaldehyde (0.05%),trans-anethole (76.39%),anisyl acetine (0.03%),caryophyllene (0.08%),hu-mulene (0,15%)and α- bulnesene (0,01%0.This incestigation will provide scientific basis for futher development and utilization of the essential oil of Limno phila rugosa.

Key words: Limnophila rugosa