Allergic airway disorders such as asthma and allergic rhinitis are mainly caused by inhaled allergen-induced improper activation and responses of immune- and non-immune cells. One important response is the production of IL-27 by macrophages and dendritic cells (DCs) during the early stage of airway allergies. IL-27 exerts powerful modulatory influences on the cells of innate immunity [e.g., neutrophils, eosinophils, mast cells, monocytes, macrophages, dendritic cells (DCs), innate lymphoid cells (ILCs), natural killer (NK) cells and NKT-cells)] and adaptive immunity (e.g. Th1-, Th2-, Th9-, Th17-, regulatory T-, CD8+ cytotoxic T- and B-cells). The IL-27-mediated signaling pathways may be modulated to attenuate asthma and allergic rhinitis. In this review, a comprehensive discussion concerning the roles carried out by IL-27 in asthma and allergic rhinitis was provided, while evidences are presented favouring the use of IL-27 in the treatment of airway allergies.