To investigate the mechanism of action of inflammatory molecules regulating the tumor microenvironment and anti-tumor through Yifei Qinghua granules and phloroglucinol-containing serum intervening in the changes of tumor microenvironment in vitro in the co-culture of lung cancer cells and bone marrow cells. A549 lung adenocarcinoma cell line and ST2 bone marrow stromal cell line were selected and a transwell chamber was used to establish the co-culture system of the two kinds of cells. They were divided into normal saline, phloroglucinol, Qifei Qinghua granule, and phloroglucinol + Yifei Qinghua granule groups. They were given drug-containing serum interventions respectively. A549 cells and ST2 cells cultured separately were used as control. Flow cytometry was used to detect the proportions of MDSCs and Tregs in bone marrow cells of ST2 cells. ELISA was used to detect the levels of inflammatory factors in the culture supernatant. Western blot was used to detect the expressions of inflammatory pathways in A549 and ST2 cells. ST2 cells and A549 cells were co-cultured. The ratio of MDSCs and Treg in ST2 cells was increased. The levels of some inflammatory factors in the culture supernatant were increased. The expression level of the inflammatory pathway in ST2 cells was increased. However, the expression level of the inflammatory pathway in A549 cells had no obvious change. While Yifei Qinghua granule and phloroglucinol could partially reverse these changes. The combination of the two was more effective than a single drug. The conversion of cells to MDSCs and Treg was accelerated after the co-culture of ST2 cells and A549 cells. The combination of Yifei Qinghua granules with phloroglucinol can reshape the tumor microenvironment, prevent this phenomenon from occurring, reduce inflammatory secretion and inhibit tumor cell growth. This may be related to the inhibition of the expressions of TNF-α/IL-1- and NF-κB/STAT3 inflammatory pathways.