in the present investigation, the essential oil compositions of four individual plants from scrophulariaceae family cultivated in vietnam were reported. the air-dried plants were hydrodistilled (vietnamese pharmacopoeia) and the oils were analyzed by gas chromatography-flame ionization detector (gc-fid) and gas chromatography-mass spectrometry (gc-ms) techniques. the essential oils content varied between 0.15% and 0.40% (v/w) on a dry weight basis. monoterpenes (74.0%-85.1) represent the main class of compound in the oils. adenosma bracteosa bon., afforded oil whose major compounds were carvacrol (37.2%), carvarol methyl ether (23.2%), -bisabolene (15.9%) and -terpinene (9.2%). the oil of adenosma indiana (lour.) merr., comprised mainly of limonene (25.1%), 1,8-cineole (20.1%) and -pinene (17.2%). however, methyl benzoate (27.7%), pulegone (23.4%) and limonene (20.2%) were the significant compounds of limnophila aromatica (lour.) merr., while limnophila micrantha (benth.) benth., gave oil whose main compounds are mentha-1,5,8-triene (38.5%) and -myrcene (24.4%).