Abstract: To explore the mechanism of major histocompatibility complex classⅠ (MHCⅠ), improve the efficiency of antigen presentation, the dimers of chicken MHC molecules were obtained. The MHCⅠ α and β₂m chain gene were linked by different length linkers with sequences encoding G₄S, (G₄S)₂, (G₄S)₃ and (G₄S)₄. Then this fragments were inserted into the eukaryotic expression vector with green fluorescent protein, and the recombinant plasmids (pEGFP-MHCⅠβ₂m-α) were constructed. The recombinant plasmids were transfected into eukaryotic cells. The gene products of recombinant plasmids were mainly located at endomembrane system of the eukaryotic cells under fluorescence microscopy. Moreover, the positive reactions were observed by Western Blot, and all the proteins had a molecular weight of about 80.0 kD, in accordance with the target proteins, and the proteins had binding reaction with specific antibodies. The results showed that the recombinant plasmids with different length linkers could be expressed in eukaryotic cells with a good immunological activity.