Trichinella spiralis,an intracellular parasite nematode,can cause severe foodborne zoonosis that is known as tichinellosis.The life cycle of T.spiralis consist of adult(Ad),muscle larvae(ML)and newborn larvae(NBL).However,no such study could be available about the protein profiles in different developmental stages of the parasite.In the present study,proteins from lysates of Ad,ML and NBL were identified by iTRAQ,respectively.The result showed that a total of 4701 proteins were identified and the number of up-regulated proteins in NBL was higher than that of other two groups.Then the protein profiles from Ad,ML and NBL were compared in pairs.Primary two clusters of the differently expressed proteins were determined with the functions regarding immune regulation and parasite invasion.Further investigation of the transcriptional levels of several genes from the differently protein profiles using quantitative PCR showed the identical results to the iTRAQ analysis.The function of these differently expressed proteins in regulation of development and host-parasite interaction should be further studied.