The immune system, its cellular and humoral response, is engaged by the host organism to fight against parasitic invasions. The group examined consisted of 52 women aged 18-42 years infected with Toxoplasma gondii. The diagnosis was established based on serologic examination. Blood for analysis was collected before antiparasitic treatment. Control group consisted of 32 healthy women aged 18-46 years. The concentrations of IgM, IgG and IgE were assayed using a set of VIDAS (bioMerieux) and the concentrations of IL-5 were assayed using a set of Quantikine human IL-5 (R&D Systems). An abnormal rise in total serum IgE can be observed in parasitosis and allergy. IL-5 is produced mainly in T-cells in response to stimulation by parasite-derived antigens and allergens The present study revealed that (in toxoplasmosis) the concentration of IgE and IL-5 contents in blood serum was higher 2-times, respectively than in healthy controls.