Interleukin 33 (IL 33),one member of the IL-1 family,is expressed in many types' tissue and regulation of multiple target cells via its suppression of tumorigenicity 2 (ST2) receptor.Therefore,the crucial roles of the novel cytokine IL-33 in allergic,endocrine diseases,infectious diseases and cancer are becoming characterized.The function of IL-33 in different parasite infection is distinctive in parasitic infections,due to the difference in pathogenic mechanism and in the time course of IL-33 expression.