© 2015 Elsevier Ltd. Background: Gingivitis is a highly prevalent periodontal disease resulting from microbial infection and subsequent inflammation. The efficacy of herbal preparations in subjects with gingivitis has been reported in some previous studies. Objective: To investigate the efficacy of a polyherbal mouthwash containing hydroalcoholic extracts of Zingiber officinale, Rosmarinus officinalis and Calendula officinalis (5% v/w) compared with chlorhexidine and placebo mouthwashes in subjects with gingivitis. Methods: Sixty patients participated in this randomized double-blind placebo-controlled trial and were randomly assigned to the polyherbal mouthwash (n = 20), chlorhexidine mouthwash (n = 20) or placebo mouthwash (n = 20). Participants were instructed to use the mouthwash twice a day (after breakfast and dinner) for 30 s for a period of two weeks. Gingival and plaque indices were assessed using MGI, GBI and MQH scales at baseline, day 7 and day 14 of the trial. Results: There were significant improvements in all assessed efficacy measures i.e. MGI, GBI and MQH scores from baseline to the end of trial in both polyherbal and chlorhexidine mouthwash groups; however, the scores remained statistically unchanged in the placebo group. MGI, BGI and MQH scores in the treatment groups were significantly lower compared with those of the control group at both day 7 and day 14 of the trial. However, there was no significant difference between the polyherbal and chlorhexidine groups, neither at day 7 nor day 14 of the trial. Polyherbal mouthwash was safe and there was neither report of adverse reactions, nor any drop-out during the course of study. Conclusion: Polyherbal mouthwash containing hydroalcoholic extracts of Z. officinale, R. officinalis and C. officinalis (5%) was effective in the treatment of gingivitis and its efficacy was comparable to that of chlorhexidine mouthwash.