The research is to investigate the anti-inflammatory effects of atractylone from rhizomes of Atractylodes macrocephala Koidzumi and mechanism by using LPS-induced microglial BV2 cells.Atractylone was extracted and the structure was identified by NMR.MTT assay was used to observe the cell viability.The content of NO in cell supernatant was measured by Griess reagent.The levels of PGE2,IL-6 and TNF-α were detected by ELISA kits.The intracellular COX-2、iNOS、MAPK、NF-κB expression was assayed by Western blot.According to the results,the levels of NO,PGE2, IL-6 and TNF-α were significantly increased induced by LPS in the supernatant of BV2 cells,however,significantly decreased by pre-treatment with atractylone.Furthermore,atractylone significantly inhibited the ERK,JNK and NF-κB expression induced by LPS in BV2 cells.It is suggested that atractylone is able to alleviate LPS-induced inflammatory responses through down-regulation of ERK,JNK and NF-κB pathways in BV2 cells．