Abstract: Objective To construct eukaryotic expression vectors using recombinant adenovirus containing the gene fragments encoding Her2/neu extracellular first ligand-binding domain(Her2-ECD),full-length extracellular domain(Her2-ECD),and extracellular and transmembrane domain(Her2-TM).Methods The cDNAs were amplified by RT-PCR and inserted into shuttle pAdTrack-CMV plasmids.Viral plasmids were obtained from homologous recombination in E.coli BJ5183,and transfected into 293 cells via liposome.Formation of viral plaque and expression of green fluorescent protein were observed by fluorescence microscopy,and the target proteins were detected by Western blotting.Results The target cDNA fragments were amplified by PCR with expected lengths and the DNA sequences were confirmed against Genbank.Formation of viral plaque,expression of green fluorescent protein and the target proteins were detected in 293 cells transfected by the viral plasmids,which showed elevated expression of Her2/neu protein with the increase of multiplicity of infection(MOI).Conclusion The eukaryotic expression vectors using recombinant adenovirus have been successfully constructed for expression of Her2/neu extracellular and transmembrane domains.