To investigate the mechanism by which Qingjie Fuzheng Granules(QFG) reverse drug resistance in human colorectal cancer HCT-8/5-FU resistant cells.Methods:HCT-8 cells and HCT-8/5-FU resistant cells were cultured，and the resistance index(RI) for different chemotherapeutic drugs and the reversal fold(RF) of QFG were calculated.The cells were divided into a blank control group(0 mg/mL) and QFG intervention groups with different concentrations(0.25，0.5，1.0 mg/mL).After 48 hours of intervention，the efflux pump function was assessed by rhodamine-123(Rho123) and doxorubicin(DOX) staining.Cell survival was evaluated by colony formation assay.Apoptosis was detected using Annexin V-FITC/propidium iodide(PI) double staining.Autophagy was analyzed using Cyto-ID staining.Protein expression levels of P-glycoprotein(P-gP)，B-cell lymphoma 2(Bcl-2)，Bcl-2-associated X protein(Bax)，selective autophagy receptor protein(p62/SQSTM1)，and microtubule-associated protein 1 light chain 3 Ⅱ(LC3-Ⅱ) were measured by Western blot.Results:HCT-8/5-FU cells showed resistance to 5-fluorouracil(5-FU)，DOX，and cisplatin(DDP).QFG effectively reversed this drug resistance.Compared with the blank control group，QFG significantly increased the average fluorescence intensity of Rho123，DOX，and Cyto-ID(all P<0.05)，inhibited cell colony formation(P<0.05)，and increased the apoptosis rate(P<0.05).QFG also reduced the protein expression of P-gP and p62(P<0.05)，decreased the Bcl-2/Bax ratio(P<0.05)，and promoted the protein expression of LC3-Ⅱ(P<0.05).Conclusion:QFG can promote apoptosis and autophagy，inhibit the efflux pump function of resistant cells，and thereby reverse multidrug resistance.