The effectiveness of cytokine-induced killer (CIK) cells for treatment of cancers has long been appreciated. Here, we report for the first time that CIK cells can be applied to treat allergic airway inflammation. Adopting from an established protocol with some modifications, we generated CIK cells ex vivo from mouse T cells, and examined their effectiveness in treatment of allergic airway inflammation using the ovalbumin-induced model of allergic airway inflammation. Based upon evaluation of bronchoalveolar lavage cellularity, T helper type2 cytokine levels and lung histology, all of which are important parameters for determining the severity of allergic airway inflammation, diseased mice treated with CIK cells showed significant reductions in all the parameters without any obvious adverse effects. Interestingly, the observed effects were comparable to those treated with dexamethasone. Thus, our study provides a novel application of CIK cells in treatment of allergic airway inflammation.