Abstract: Objective：To investigate the role of the Janus kinase/signal transducers and activators of transcription（JAK/STAT）signaling pathway in infection of EV71. Methods：The mRNA levels of 4 interferon stimulated factors(ISGs) including ISG15,ISG56,OAS1,MXA in human rhabdosarcoma(RD) cells and human monocyte macrophagic leukemia cell line(THP-1) were detected by RT-PCR. The effect of IFN-α2b(1 000 U/mL) on the infection and replication of EV71 were also observed, and the total and phosphorylated level of STAT1 were analyzed by western blot. Results：The expression of MXA mRNA decreased in EV71 infected RD cells, but no phosphorylated STAT1 was found. The expression of MXA, OAS1 and ISG56 mRNA and phosphorylated STAT1 level were increased in EV71 infected THP 1cells. Compared with IFN group, the levels of ISG15, ISG56, OAS1 and MXA mRNA, as well as phosporylated STAT1 were decreased in the EV71 infected RD cells treated with IFN-α2b. The expressions of 4 ISGs and phosphorylated STAT1 level significantly were elevated in THP-1cells. Conclusion：Infection of EV71 could block JAK/STAT signaling pathway in RD cells and the opposite results were observed in THP-1 cells. These results suggest that THP-1 cells might play a role in innate immune response in the patients infected with EV71.