Objectives : The purpose of this study was to evaluate on the antimicrobial effect on the periodontal pathogens and anti-inflammatory effect of Artemisiae Iwayomogii Herba. Artemisiae Iwayomogii Herba has been used for treating as Artemisiae Capilaris Herba in Korea. Methods : Artemisiae Iwayomogii Herba was prepared by extracting medicinal herb with water. We investigated antimicrobial activity by the minimun inhibitory concentration (MIC) test. We also investigated inhibition of IL-$1{eta}$-induced collagenase-l(MMP-l), stromelysin-1(MMP-3), interleukin-6 gene expression in human gingival fibroblasts. Results : The antimicrobial effect of Artemisiae Iwayomogii Herba was evaluated with MIC against periodontopathogens; Porphyromonas gingivalis 2561, W50, A7A1-28, 9-14K-1, Prevotella intermedia28, and Actinobacillus actinomycetemcomitans Y4, MICs of Artemisiae Iwayomogii Herba were 0.156 mg/ml, 0.625 mg/ml, 0.313 mg/ml, 1.25 mg/ml, 10 mg/ml and 10 mg/ml. The anti-inflammatory effect of Artemisiae Iwayomogii Herba was evaluated with Influence of herbs on the IL-$1{eta}$-induced expression of MMP-1, MMP-3, interleukin-6, IL-$1{eta}$ increased MMP-1, MMP-3, interleukin-6 mRNA levels. Artemisiae Iwayomogii Herba significantly inhibited IL-$1{eta}$-induced MMP-1, MMP-3, interleukin-6 gene expressions in a dose-dependent manner. Conclusions : These results suggested that Artemisiae Iwayomogii Herba might reduce the excessive proteolytic capacity of the gingival fibroblast during inflammation and could be developed a new drug in periodontitis.