【Objective】The study aimed to explore the influence of fowl adenovirus serotype 4(FAdV-4) protein Ⅷ(pⅧ) on expression innate immune-associted genes of host, providing a reference for further study of the pathogenesis of FAdV-4.【Method】FAdV-4Ⅷ gene coding sequence(CDS) was amplified by PCR,linked to pEF1α-HA eukaryotic expression vector, and recombinant expression plasmid pEF1α-HA-Ⅷ was constructed. Recombinant expression plasmid pEF1α-HA-Ⅷ(experimental group) and empty plasmid pEF1α-HA(control group) were transfected into LMH cells, and the expression of protein Ⅷ was verified by Western blotting and indirect immunofluorescence, real-time florescence quantitative PCR was used to detected the expression levels of STING, MDA5, TBK1, MAVS, NF-κB, IRF7, IFN-α, INF-β, IL-6, IL-8, IL-15, IL-1β.【Result】The open reading frame(ORF) length of Ⅷ gene was 744 bp, encoding 247 amino acid residues, recombinant protein Ⅷ can react with HA-tag monoclonal antibody from mouse, a single band was obtained at 34 kD, and green fluorescence was observed by immunofluorescence detection, indicating that recombinant protein Ⅷ was well expressed in LMH cells. Compared with the control group, after the recombinant protein Ⅷ was expressed in LMH cells, the expression level of the mode receptor STING gene was significantly increased by 5.6 times(P＜0.05, the same as below), and the expression level of MDA5 gene was increased by 30%. The gene expression levels of adaptor protein TBK1 and MAVS genes were significantly increased by 1.5 and 2.4 times compared with the control group, respectively. The level of transcription factor IRF7 was significantly increased by 3.4 times, and the expressions of NF-κB genes were suppressed. Meanwhile, the expression levels of interferon(IFN-α and IFN-β) and interleukin(IL-6, IL-8, IL-15 and IL-1β) were up-regulated, and IFN-α and IFN-β were extremely significantly up-regulated 19.2 and 14.4 times(P＜0.01), respectively. IL-6, IL-8, IL-15 and IL-1β were significantly up-regulated 4.1, 2.1, 6.0 and 7.9 times, respectively.【Conclusion】Overexpression of FAdV-4 pⅧ leads to up-regulated expression of STING, MDA5, TBK1, MAVS, IRF7, IFN-α,IFN-β, IL-6, IL-8, IL-15 and IL-1β in LMH cells. The results indicate that protein Ⅷ can promote the natural immunity of host stimulated by FAdV-4 to a certain extent. [ABSTRACT FROM AUTHOR]