Parasite is derived foreign molecules which can be recognized by the immune system. Parasite released antigens from: the excretory/secretory antigens, when worm dies and destroyed and antigens of intracellular which expressed on the surface of the host cell during its intramuscular phase. Some parasites living in the intestine can stimulate strong immune responses because their antigens being taken up across the mucosa, but others appear less immunogenic. Other parasites released antigens that act as allergens which stimulate the formation of IgE and thus host develops hypersensitivity to the parasite. So, this book aimed to help medical and medical laboratory students to understand how parasitic infections are controlled. Besides, the book gives the students idea and knowledge about immunological diagnosis of the parasitic infections. The book covers the topics related to titration methods, agglutination reactions, DAT for Leishmania, rapid diagnostic tests, Cells separation or PBMCs, Culture and cryopreservation, ELISA, Toxoplasma serological profile, Direct skin test, IF, CFT, IHAT, Precipitation Immunoassay, Western immunoblotting, Flow cytometry technique.