To study the immunomodulatory effects of Radix Pseudostellariae fibrous root saponins (RPFRS) and their mechanisms,we examined the effects of RPFRS in RAW 264.7 cells on the proliferation,phagocytic activity,production of NO and cytokines,the mRNA expression of immune molecules and relevant immune protein expression levels.RAW 264.7 cells were treated with different concentrations of RPFRS.A DMEM blank control group (control group) and LPS positive group (LPS group) were set at the same time.The results showed that compared with the control group,the OD values on phagocytosis of neutral red (P<0.01),the contents of NO,IL-6 and the mRNA expression levels of IL-6,TNF-α in the RPFRS groups were significantly increased in a dose-dependent manner.The contents of IL-10,IL-1β,TNF-α and the mRNA expression levels of IL-10,IL-1β,iNOS,MyD88 and NF-κB increased significantly in the RPFRS groups (P<0.05) when the RPFRS concentration was 12.5-100 μg/mL,but the mRNA expression of TLR4 decreased in a dose-dependent manner (P<0.05).At the same time,Western blotting results also showed that RPFRS can increase the expression of TLR2,MyD88,TRIF,and nuclear NF-κB protein,while the expression of TLR4,IκB-α and cytosolic NF-κB protein was decreased. Above results indicated that RPFRS could enhance the immunity of RAW 264.7 cells by increasing their proliferation capacity, phagocytic activity and the ability to secrete NO and cytokines. And the mechanism of immune recombination of RPFRS on RAW 264.7 cells might be through the TLR2/4-MyD88/TRIF-NF-κB pathway to activate RAW264.7 cells.