We investigated the anti-obesity effect of the aerial part of Artemisia scoparia Waldst. et Kit. (Compositae). An 80 % aqueous EtOH extract of the aerial part inhibited triglyceride (TG) accumulation and the nitric oxide (NO) production activity. A new chromane derivative was isolated from the aerial part of A. scoparia Waldst. et Kit. along with 18 known compounds. The structure of the new chromane, scopariachromane ( 1), was elucidated by spectroscopic analyses. The inhibitory effects of the compounds on TG accumulation activity were examined. Among these, cirsiliol ( 11) inhibited TG accumulation in 3T3-L1 preadipocytes. Jaceosidin ( 12) inhibited NO production in a murine macrophage-like cell line (RAW 264.7). These results indicate that the 80 % aqueous EtOH extract and compounds isolated from the aerial part of A. scoparia Waldst. et Kit. may improve obesity-related insulin resistance.