Down-regulation of microglial activation represents a practical strategy for combating diverse brain disorders such as stroke and neurodegenerative diseases. In the present study, we showed evidence that isopropyl 3-(3, 4-dihydroxyphenyl)-2-hydroxypropanoate (IDHP), a new bioactive metabolite of Danshen (Salvia miltiorrhiza Bunge), exerted an anti-inflammatory effect in lipopolysaccharide (LPS)-induced microglia. Our data showed that IDHP significantly reduced the production of nitric oxide (NO), tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) in LPS-induced BV-2 cells and rat primary microglia in a dose-dependent manner. IDHP also suppressed mRNA expression of LPSinduced inducible nitric oxide synthase (iNOS), TNF-αand IL-1β. Moreover, IDHP significantly suppressed the production of reactive oxygen species (ROS), nuclear factor κB (NF-κB) translocation and DNA binding activity induced by LPS treatment in BV-2 cells. These findings indicated that IDHP might be of value in the treatment of various microglia-mediated neuroinflammatory diseases.