Abstract: Total RNA was isolated from neijiang pig peripheral blood lymphocytes which were stimulated with ConA. Then the pIFN-γ cDNA was amplified by reverse transcription polymerase chain reaction. The amplified fragment was cloned into vector pMD18-T named pMD-N-IFN-γ and then sequenced. It was found that the amplified fragment was consisted of 603 nucleotides, the ORF consisted of 501 nucleotides, encoding 166 amino acids, Neijang pig IFN-γ gene has more than 99.4% homology with other pigs on Genbank. Subcloning the ORF of pig IFN-γ gene， then the sub-cloned gene was successfully inserted between EcoRI and XhoI site of the eukaryotic expression vector pcDNA3.1(+)， named pcDNA3.1(+)-N-IFN-γs.

Key words: IFN-γ; cloning; sequencing; constructing eukaryotic expression vector