With the completion of sequencing of the genomes of Drosophila melanogaster, Bombyx mori, Apis mellifera， Anopheles gambiae, etc., proteomic technology has been an important tool to clarify their functions. This article reviewed the achievements obtained by application of differential proteomic technology to the fields containing insect induced immunity, resistance mechanism and molecular pathology:  (1) Changes in protein expression files in insect hemolymph and hemocyte cell line induced by bacteria, fungi or injecting; (2) Differential proteins in brush board membrane between Bt-resistant and susceptible insects or in salivary gland between resistant and susceptible sand fly to Leishmania chagasi; (3) Alteration in proteins between the insect treated by chemical pesticide or the hemolymph of insect induced by polydnavirus and control insect.  Finally, the problems and strategies of insect differential proteomics have been discussed.