The bark of the root and stem of Ulmus davidiana var. japonica has been used as a traditional Korean medicine to treat inflammatory disorders. This plant reportedly exhibits antioxidant, anticancer, and anti-inflammatory effects. A search for biologically active compounds in U. davidiana var. japonica extracts yielded bakuchiol, which we structurally identified on the basis of spectral data, including two-dimensional nuclear magnetic resonance spectroscopy and distortionless enhancement by polarization transfer. In our study, bakuchiol (50 microM) inhibited lipopolysaccharide-induced nitric oxide and prostaglandin E(2) production in RAW 264.7 macrophages by 53.7% and 84.2%, respectively. These results suggested that bakuchiol is one of the potent anti-inflammatory components of U. davidiana var. japonica.