The essential oil of the dried flowering aerial parts of Lallemantia iberica Fisch. et C.A. Mey. (Labiatae), collected from the suburb of Larijan, north of Iran, in July 2003, was isolated by hydrodistillation and analyzed by means of GC and GC/MS. Among the 26 components identified in this oil, p-cymene (22.1%), isophytol (19.8%), T-cadinol (11.1%), 3-octanol (8.1%), caryophyllene oxide (7.4%) and terpinen-4-ol (5.7%) were the major constituents.