AimsThis study aimed to investigate the effects of Umbelliferone (UMB) on the inflammation underlying alveolar bone resorption in mouse periodontitis.MethodsMale Swiss mice subjected to a ligature of molars were grouped as non‐treated (NT), received UMB (15, 45, or 135 mg/kg) or saline daily for 7 days, respectively, and were compared with naïve mice as control. Gingival tissues were evaluated by myeloperoxidase (MPO) activity and interleukin‐1β level by ELISA. The bone resorption was directly assessed on the region between the cement–enamel junction and the alveolar bone crest. Microscopically, histomorphometry of the furcation region, immunofluorescence for nuclear factor‐kappa B (NF‐ĸB), and immunohistochemistry for tartrate‐resistant acid phosphatase (TRAP), and cathepsin K (CTSK) were performed. Systemically, body mass variation and leukogram were analyzed.ResultsPeriodontitis significantly increased MPO activity, interleukin‐1β level, and NF‐ĸB+ immunofluorescence, and induced severe alveolar bone and furcation resorptions, besides increased TRAP+ and CTSK+ cells compared with naïve. UMB significantly prevented the inflammation by reducing MPO activity, interleukin‐1β level, and NF‐ĸB+ intensity, besides reduction of resorption of alveolar bone and furcation area, and TRAP+ and CTSK+ cells compared with the NT group. Periodontitis or UMB treatment did not affect the animals systemically.ConclusionUMB improved periodontitis by reducing inflammation and bone markers.