Object To analyze the constituents and build up the fingerprint spectrum of Atractylodes macrocephala Koidz. Methods The essential oil was extracted by water distillation method and seeping method and analyzed by GC-MS,heuristic evolving latent projections (HELP) resolution method. The fingerprints difference of A. macrocephala from various habitats were compared. Results Water distillation method was good for the extraction of essential oil. The HELP method can greatly improve the reliability of the qualit...