Abstract: The present invention discloses the application of cyathane diterpenoids in preparation of drugs for treating neuroinflammation. Seven cyathane diterpenoids 1-7 can significantly prevent LPS-induced BV-2 microglia from producing NO. The most active compound as 6 can reverse M1/M2 polarization of the microglia. 6 inhibits the pro-inflammatory proteins including iNOS and COX-2 through MAPK/NF-?B signaling pathways and promote the anti-inflammatory factors including IL-10 and ARG-1. An application prospect of the anti-inflammatory cyathane diterpenoids in the treatment of the neurodegenerative diseases is achieved.