Retention of inflammatory mediators and cells in the middle ear cleft in otitis media with effusion(OME) results in inflammation and hearing loss. Cytokines, potent regulators and mediators of the immune response, are glycoprotein produced by macrophage and other cells, and induce fever production, fibroblast and cytotoxic cell activation, regulation of antibody formation and endothelial cell growth. We measured the levels of interleukin 2(IL-2), interleukin 4(IL-4) and interleukin 7(IL-7) in OME using enzyme-linked immunosorbent assays(ELISA) and interleukin 2 receptor(IL-2R, CD25) using flow cytometry. Positive level was considered to be only middle ear effusion(MEE) in which cytokines were detectable near or above the level of the lowest standard provided with the kits. The mean levels of IL-2, IL-4 and IL-7 were 48.20pg/mg IgG, 9.64±2.13pg/mg IgG, 88.50±26.20pg/mg IgG in serous type and 67.15±21.61pg/mg IgG, 29.55±22.14pg/mg IgG, 73.24±47.88pg/mg IgG in mucoid type. Positive levels of IL-2, IL-4 and IL-7 were found in 50%, 33% and 47% of MEE. Mean level of IL-2R was 5.41±8.12% and it did not show a significant difference according to the type of MEE. The results suggest that IL-2 and IL-4 may play a role of immunoregulator in the middle ear cleft in persistent OME while IL-7 may be an important regulator in the early stage of OME.