main chemical compositions of essential oil (eo) from litsea cubeba fruit collected in kon tum province of vietnam were geranial (32.0%), neral (24.3%), citronellal (14.2%), and limonene (10.1%). twenty-four compounds of the eo were identified and compared with those from eos previously reported in india, china, and malaysia. minimal inhibitory and bactericidal concentrations (mic and mbc) indicated that the eo induced high levels of growth inhibition and moderate bactericidal activity against seven test helicobacter pylori strains, including six strains resistant to one to four antibiotics, azithromycin, erythromycin, levofloxacin, and metronidazole. the bacterial biofilm formation was significantly suppressed by the eo at 1/2 and 3/4xmic. the eo also exerts inhibitory activity against h. pylori-urease and convert a spiral form of h. pylori into a coccoid form. fruit eo inhibits bacterial growth via both contact and fumigant action.