We investigated the possible beneficial effects of curcumin (CMN) in the treatment of sinusitis. An experimentally induced sinusitis model was created in rats, and the results were evaluated histologically. Thirty-two healthy, female Sprague Dawley rats weighing 270 to 310 g each, were randomly divided into four groups. Group 1 was the control group. In Groups 2 to 4, experimentally induced acute sinusitis was developed, and the rats in those groups were given saline, sulbactam-ampicillin, and CMN, respectively, for 10 days. Then all rats were dissected, and samples of sinus mucosa were taken. Histologic examination was performed via light microscopy. In the sinusitis + antibiotic group, values of inflammation, vascular congestion, vascular dilatation, and subepithelial glandular atrophy were significantly higher; and values of mucosal damage and cilia loss, and hyperplasia of goblet cells, were not significantly different from those in the control group. In the sinusitis + CMN group, values of inflammation, vascular congestion, and vascular dilatation were significantly higher; and values of mucosal damage and cilia loss, hyperplasia of goblet cells, and subepithelial glandular atrophy were not significantly different from those of the control group. Histologic examination revealed that in the sinusitis + CMN group, a nearly normal appearance of the epithelial tissue and reduced cellular inflammation in connective tissue were observed. Minimal vascular congestion in connective tissue remained. The efficacy of CMN in acute sinusitis may be related to its potent anti-inflammatory effects on modulation of various inflammatory cytokines. When low side effects are taken into account, CMN therapy may be a promising option in the treatment of acute sinusitis.