Objective:to study the preparation and chemical composition analysis of volatile oils from different parts of flower, stem and leaf of north Elsholtzia ciliata. Methods: volatile oils was prepared by steam distillation, the chemical constituents of the volatile oils of Elsholtzia ciliata by steam distillation were identified by GC-MS, and the antibacterial effects were investigated by disk method. Results: the higher contents of Elsholtzia ciliata flowers, stems and leaves were BETA-dehydrogenated elsholtzone, 1,1'-[ethylenebis (oxy)] dibutane and BETA-dehydrogenated elsholtzone, respectively. The results of bacteriostatic experiment showed that the volatile oils of three parts had different inhibitory effects on Staphylococcus aureus, Bacillus subtilis, Bacillus brevis and Candida albicans. Conclusion: the volatile oils of three parts have different chemical compositions and antibacterial activities. This study provides basis for the development and utilization of the volatile oil of north Elsholtzia ciliata.