Abstract: The aim of this study is to investigate the efficacy of Calendula officinal extract toothpaste in reducing gingival inflammation and plaque formation. A total of 40 volunteers with established gingivitis (21 males and 19 females, with a mean age of 28.8±3.28) were included in this prospective, double blind clinical study. They were randomly assigned to 2 treatment groups: group 1 (n = 20), treated with a base dentifrice as the control toothpaste; group 2 (n = 20), treated with Calendula flower extract tooth paste. Subjects were instructed to brush their teeth three times daily using the Bass method and their assigned tooth paste for 4 weeks. Data was collected at baseline and at increment of 2, 3 and 4 weeks. This data includes an analysis of Plaque Index (PI), Gingival Index (GI) and Bleeding on Probing (BoP). The present study was carried out at Babol Dental School, Babol, Iran between December 2007 and October 2008. Over a period of 4 weeks, all indices were significantly decreased. A substantial reduction in PI was noted for group 2 (1.63 vs. 1.42) throughout the follow-up period, this reduction was seen in GI (1.23 vs. 0.66) and BoP (1.29 vs. 0.64) for group 2. Brushing with calendula toothpaste led to significant reductions in PI, GI and BoP. This treatment could therefore, be recommended as an adjunctive procedure effective for the improvement of gingival inflammation.