Histamine-releasing factor (HRF) consists of a group of cytokines that can cause basophil/mast cell to release histamine, however, the composition of HRF still remains undefined. This study was designed to measure the concentrations of chemokines in asthmatic children receiving immunotherapy. Peripheral blood mononuclear cells culture supernatants were obtained from six asthmatic children before and four, eight months after immunotherapy (IT). The levels of monocyte chemotactic and activating factor (MCAF), macrophage inflammatory protein-1a (MIP-1a), regulated on activation normal T-cell expressed and secreted (RANTES) and interleukin-8 (IL-8) spontaneously and after stimulation with PHA and mite allergen in the supernatants. The data showed: 1) The levels of MCAF and MIP-1a increased four months, and decreased eight months, after IT; 2) By contrast, the level of RANTE increased after IT; 3) The level of IL-8 also tended to increase after IT. Abnormal chemokine production may contribute to the pathogenesis of bronchial asthma and restoration of normal chemokine production may be used to partially explain the clinical efficacy of immunotherapy.