Abstract: To explore MHC mechanism presenting antigen and function as vaccine carrier，we cloned MHCⅠgene from chicken by RT-PCR，and constructed a recombined plasmid containing MHCⅠβ_2m-α fusion gene and expressed in a prokaryotic system. Chicken MHCⅠα and β_2m chains were cloned from chicken by RT-PCR，the recombinant gene MHCⅠβ_2mα was linked with a DNA sequence coding for short peptide（Gly₄Ser）₄，and confirmed by PCR amplification，double restriction digestion and DNA sequencing. The recombinant plasmid was expressed in E.coliBL21 after induction by IPTG. SDS-PAGE and Western blotting were used to detect expression products. The results revealed that the lengths of MHCⅠα and β_2m chains were 1014 and 300 bp，respectively, and the recombinant fusion gene was 1194 bp. The fusion protein was about 62.0 ku and had the reactinogenicity with specific antibody.

Key words: chicken MHCⅠα chain; chicken MHCⅠ β_2m chain; fusion protein