Objective:To explore the effects of IL-6 on the expression of Toll like receptor-4(TLR4) of THP-1. Methods:Flow Cytometry(FCM) was used to detect the expression of TLR4 of THP-1 cells,which was stimulated with different concertrations of IL-6(0 ng/L,10 ng/L,100 ng/L,1 μg/L,10 μg/L and 100 μg/L),and on different time after treated with 10 μg/L IL-6 (0 h,3 h,6 h,12 h,24 h,48 h). Results:Different concertrations of IL-6 can significantly promote the expression of TLR4 in THP-1 cells,especially under the concentration of 10 μg/L IL-6 group. Still this effect can be observed in 10 μg/L IL-6 group under treated for 3 h, 6 h,12 h,24 h and 48 h,especially at 24 h. Conclusion:The expression of of TLR4 on THP-1 cells can be promoted by IL-6 in a dose-and time-dependence.