Abstract:Regarding to the parasitoid-host interactions, the investigation of molecular mechanisms of parasitoid circumventing host defense system and manipulating host development is a focal researching point in the biological control area. To disrupt hosts cellular immune response, parasitoids are capable of controlling the transcriptional and signal factors critical for hemocyte proliferation and differentiation, regulating the factors involved in hemocyte encapsulation and spreading, and inducing hemocyte apoptosis. To suppress host humoral immune defense, they are able to intervene in the expression of hemolymph melanization related genes and antibacterial peptide genes. To disturb host development, they are with the ability to modulate the proteins and enzymes key to development. In this article, we present a brief overview of the recently documented information concerning these studies.