Abstract: The present research is to explore the protective effects and mechanism of ursolic acid (UA) on THP-1 cells.The effects of UA at different concerntration (10,30,50μmol/L,respectively) on THP-1 adhesion and migration capability were observed after cell inflammation model induced by lipopolysaccharide.The mRNA expression of MCP-1 and CCR2 was detected by RT-PCR.Moreover,the effect of UA on NF-κB activity was investigated. Compared with the model group,UA (30 and 50μmol/L) significantly decreased the cell adhesion to fibronectin.All dosages of UA significantly inhibited THP-1 cells migration.In the meantime,UA downregulated the expression of MCP-1 and CCR2 and mediated NF-κB activity.Therefore,UA exerts its protective effects on THP-1 cells by,partly at least,the inhibition of NF-κB activity accompanied with decreased MCP-1 and CCR2 expression.