Abstract: Objective: To analyze the effect of salvianolic acid B on biological function of aging macrophages through phosphatidylinositol-3 kinase (PI3K)/threonine protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathways. Methods: The bone marrow macrophages of mice were studied as subjects, and the models of aging macrophages were established with 3% hydrogen peroxide solution. The experiment included the control group,the aging group and the salvianolic acid B groups. The control group consisted of non-aging macrophages;the aging group consisted of aging macrophages,and the salvianolic acid B groups consisted of aging macrophages treated with salvianolic acid B, and the intervention concentrations were 10 μmol/L, 50 μmol/L and 100 μmol/L, respectively. Cell activity was detected by Cell Counting Kit 8 (CCK-8); the expression of inflammatory factors was detected by Quantitative Real-time Polymerase Chain Reaction (qRT-PCR); the polarization of aging macrophages towards M1 and M2 types was detected by immunodual fluorescence method, and the expressions of PI3K, AKT and mTOR were detected by Western Blot (WB). Results: From 0 hours to 72 hours, the detected Optical Density (OD) values of each group increased gradually. At 72 hours, the proliferative activity of macrophages in the aging group was lower than that in the control group (P<0.05). Compared with that in the aging group,the proliferation activity of macrophages was higher than that in the 10 μmol/L, 50 μmol/L and 100 μmol/L salvianolic acid B groups (P<0.05). The proliferation activity of macrophages in the 100 μmol/L and 50 μmol/L salvianolic acid B groups was higher than that in the 10 μmol/L salvianolic acid B group (P<0.05). The proliferation activity of macrophages in the 100 μmol/L salvianolic acid B group was lower than that in the control group, the difference being not significant (P>0.05). Compared with those in the control group, the relative expressions of interleukin (IL) -1β, inducible nitric oxide synthase (iNOS), tumor necrosis factor- α (TNF- α) in the aging group and the 100 μmol/L salvianolic acid B group were increased (P<0.05), while the relative expressions of IL-4, IL-10 and Arginase 1 (Arg1) were decreased (P<0.05). Compared with those in the aging group, the relative expressions of IL-1β, iNOS and TNF- α in the 100 μmol/L salvianolic acid B group were decreased (P<0.05), while the relative expressions of IL-4, IL-10 and Arg1 were increased (P<0.05). Compared with those in the aging group, the CD206 expression was up-regulated and the CD86 expression was down-regulated in the 100 μmol/L salvianolic acid B group. Compared with those in the control group , the expression levels of p-PI3K , p-AKT and p-mTOR in the aging group were increased (P<0.05). Compared with those in the aging group, the expression levels of p-PI3K, p-AKT and p-mTOR in the 100 μmol/L salvianolic acid B group were decreased (P<0.05). The expression of p-PI3K in the 100 μmol/L salvianolic acid B group was higher than that in the control group (P<0.05),but there were no significant differences in the expressions of p-AKT and p-mTOR when compared with those in the control group (P>0.05). Conclusion:Salvianolic acid B can enhance the proliferation activity of aging macrophages and promote their M2-type polarization through PI3K/AKT/mTOR signaling pathways.