The aim of this study is to explore anti-inflammatory phytochemicals from based on the inhibition of pro-inflammatory enzyme, human neutrophil elastase (HNE) and anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage. Three stereoisomers of iridal-type triterpenoids ( - ) were isolated from the roots of and their stereochemistries were completely identified by NOESY spectra. These compounds were confirmed as reversible noncompetitive inhibitors against HNE with IC values of 6.8-27.0 µM. The binding affinity experiment proved that iridal-type triterpenoids had only a single binding site to the HNE enzyme. Among them, isoiridogermanal ( ) and iridobelamal A ( ) displayed significant anti-inflammatory effects by suppressing the expressions of pro-inflammatory cytokines, such as iNOS, IL-1β, and TNF-α through the NF-κB pathway in LPS-stimulated RAW264.7 cells. This is the first report that iridal-type triterpenoids are considered responsible phytochemicals for anti-inflammatory effects of .