Abstract: The IgG, IgA, IgM levels in sera of 51 patients suffered from pulmonary acariasis and the serum IgE level in 16 of them were determined using single immunodiffussion technique or biotin-avidin enzyme immunosorbent assay (ABC-ELISA). The results showed that the IgM level of the patients was approaching to that of the normals while IgG (169.77±46.91U/ml), IgA (308.39±91.83U/ml) and IgE (458.90±273.64U/ml) levels of the patients increased significantly. This suggests that some components of mites may have stimulated the humoral immunoreactions of the host.