The entire pig aminopeptidase N (pAPN) gene was amplified by RT-PCR using total RNA extracted from intestinal brush border membrane of a newborn piglet. The amplified products of the pAPN gene were cloned into the vector pMD18-T, generating a recombinant plasmid pMD18-T-pAPN. The C subunit of pAPN (pAPN-C) produced by PCR from the plasmid pMD18-T-pAPN was expressed in Escherichia coli using vector pET-32a with His tag. After confirming reactivity of the recombinant protein pAPN-C to antibody against native pAPN, polyclonal antibody against the recombinant protein pAPN-C was prepared in rabbit using purified protein as immunogen. In Western blot analysis, the antibody elicited by the recombinant protein pAPN-C could recognize the native pAPN. These data demonstrate that the pAPN-C recombinant protein and its polyclonal antibody can provide some basis for further receptor antagonist.