Objective:To explore the immunogenicity of severe fever with thrombocyte-penia syndrome virus(SFTSV)glycoprotein Gn. Methods:SFTSV glycoprotein Gn gene and optimal Gn gene were amplified by polymerase chain reaction(PCR)respectively. The gene product were cloned to pJW4303 to construct recombinant plasmids and all constructs were identified by sequencing,and then transiently transformed into HEK293T cells to measure the Gn expression by Western blot. We immuned the BALB/c mice with recombinant plasmids and blank vector,and verified its immunogenicity by enzyme-linked immunosorbent method. Results:The recombinant plasmids pJW4303-WSP-Gn and pJW4303-tPA-Gn-opt were constructed success-fully. The pJW4303-WSP-Gn transiently expressed Gn antigen in cell lysates of HEK293T cells in vitro,and pJW4303-tPA-Gn-opt in supernatants as same as cell lysates. The specific IgG antibodies induced by pJW4303-tPA-Gn-opt was earlier and higher than that of pJW4303-WSP -Gn. Conclusion:SFTSV glycoprotein Gn showed good immunogenicity. The recombinant plasmid pJW4303-tPA-Gn-opt promoted the synthesis and secretion of Gn,and showed better humoral immunogenicity than pJW4303-WSP-Gn.