Previous studies have shown that Magnoliae cortex and Ginkgo biloba extracts were showed on the antimicrobial and anti-inflammatory action, in vitro. The purpose of this study was to evaluate on the effect of antimicrobial and anti-inflammatory activity of Magnoliae cortex and Ginkgo biloba extracts containing dentifrice in gingivitis. 70 subjects with gingivitis were divided into an experimental group which performed normal oral hygiene procedure with Magnoliae cortex and Ginkgo biloba extracts containing dentifrice and a control group which also performed normal oral hygiene procedure with the same dentifrice without the natural extracts and completed a doubleblind, cross-over study. At baseline and 3 weeks, subjects were assayed for clinical study by plaque index, gingival index, pocket depth, GCF rate, and microbiological study by subgingival dental plaque bacterial morphotypes by phase contrast microscopy, total anaerobes, total aerobes, Black pigmented bacteroides, A.actionomycetemcomitans, A.viscosus, C.rectus, Ssenguis; P.gingivalis, P.intennedia by bacterial culture and immunofluorescence microscopy. After 3 weeks using their respective dentifrices, reductions in the clinical indices of subjects were similar between the experimental dentifrice group and a control dentifrice group except for statistically significant much reductions in PI, GI, and GCF rate in the experimental dentifrice group as compared to control dentifrice group. Also statistically significant reductions in the motile rods and Spirochetes were found in both experimental group to compare with control group, however statistically much reduction in total anaerobes, Black pigmented bacteroides, and P.gingivalis, P.intennedia were found in the experimental dentifrice group as compared to control dentifrice group. This results indicates that Magnoliae cortex and Ginkgo biloba extracts containing dentifrice might be useful for elimination of gingival inflammation.