Abstract: The porcine prothymosin α (ProTα) cDNA fragment was amplified from kidney of porcine by reverse transcriptionpolymerase chain reaction (RTPCR). Sequence analysis showed that the complete open reading frame (ORF) of ProTα gene includes 333 bp and encodes 109 aa. The sequence shared 99.4% homology with the two published ProTα genes. pET32mProTα was constructed by gene rearrangement, then it was transformed into E. coli Rosetta 2 (DE3). SDSPAGE electrophoresis analysis showed that the fusion protein of ProTα molecular mass was about 12 070 of molecular weight. MTT essay confirmed that it can enhance lymphocyte proliferation obviously.