Two new Tricholoma terpenoids, tricholopardins A and B, were isolated from the fruiting bodies of the basidiomycetes Tricholoma pardinum. Their structures were elucidated by spectroscopic methods, as well as electronic circular dichroism and optical rotatory dispersion calculations. Tricholopardin A potently inhibited nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages with an IC<sub>50</sub> of 0.08 μM. Its anti-inflammatory effects on three inflammatory mediators were also evaluated. A plausible biosynthetic pathway for these products is discussed.