The therapeutic effects of umbelliferone (30, 60 and 90 mg/kg), a coumarin isolated from Typha domingensis (Typhaceae) were investigated in a mouse model of bronchial asthma. BALB/c mice were immunized and challenged by nasal administration of ovalbumin. Treatment with umbelliferone (60 and 90 mg/kg) caused a marked reduction of cellularity and eosinophil numbers in bronchoalveolar lavage fluids from asthmatic mice. In addition, a decrease in mucus production and lung inflammation were observed in mice treated with umbelliferone. A reduction of IL-4, IL-5, and IL-13, but not of IFN-gamma, was found in bronchoalveolar lavage fluids of mice treated with umbelliferone, similar to that observed with dexamethasone. The levels of ovalbumin-specific IgE were not significantly altered after treatment with umbelliferone. In conclusion, our results demonstrate that umbelliferone attenuates the alteration characteristics of allergic airway inflammation. The investigation of the mechanisms of action of this molecule may contribute for the development of new drugs for the treatment of asthma.