AIM　To detect chemical components of the essential oil of Schisandra chinensis(Turcz.)Baill.. METHODS　The essential oil was analyzed with GC/MS, heuristic evolving latent projections(HELP) resolution and overall volume integration method. RESULTS　HELP method along with the data from GC/MS can be used to conduct the peak purity examination and resolution of overlapping peaks to obtain pure chromatogram and MS spectrum of each component. Fifty six components were separated and 49 of them were qualitatively and quantitatively analyzed. All the components represent about 98.27% of the total content. CONCLUSION　The resolved pure chromatogram and MS spectrum can greatly enhance the reliability of similar searches in the commercial MS database and thus contribute to the accuracy of the qualitative and quantitative analysis of the essential oil.