The World Health Organization reports that 235 million people are currently affected by asthma. This disease is associated with an imbalance of Th1 and Th2 cells, which results in the upregulation of cytokines that promote chronic inflammation of the respiratory system. The inflammatory response causes airway obstruction and can ultimately result in death. In this study we evaluated the effect of 1'-acetoxychavicol acetate (ACA) isolated from Alpinia galanga rhizomes in a mouse model of ovalbumin (OVA)-induced asthma. To generate the mouse model, BALB/c mice were sensitized by intraperitoneal injection of OVA and then challenged with OVA inhalation for 5 days. Mice in the vehicle control group were sensitized with OVA but not challenged with OVA. Treatment groups received dexamethasone, 25 mg/kg/day ACA, or 50 mg/kg/day ACA for 5 days. Asthma-related inflammation was assessed by bronchoalveolar lavage fluid cell counts and histopathological and immunohistochemical analysis of lung tissues. Our results showed that ACA reduced the infiltration of white blood cells (especially eosinophils) and the level of IgE in the lungs of mice challenged with OVA and suppressed histopathological changes such as airway remodeling, goblet-cell hyperplasia, eosinophil infiltration, and glycoprotein secretion. In addition, ACA inhibited expression of the Th2 cytokines interleukin (IL)-4 and IL-13, and Th1 cytokines IL-12α and interferon-γ. Because asthmatic reactions are mediated by diverse immune and inflammatory pathways, ACA shows promise as an antiasthmatic drug candidate.