To observe the efficacy of Qizhu Formula in treating non-alcoholic fatty liver disease(NAFLD) with spleen deficiency and damp-heat syndrome and explore its mechanism of action based on serum metabolomics changes.Methods:A total of 31 NAFLD patients with spleen deficiency and damp-heat syndrome treated at Nanjing Hospital of C.M.and Jiangsu Province Hospital of Chinese Medicine from July 2018 to August 2023 were enrolled as the observation group.Twenty-one healthy individuals randomly selected from the physical examination center of Jiangsu Province Hospital of Chinese Medicine during the study period served as the control group.NAFLD patients received lifestyle interventions such as dietary adjustments，exercise，and psychological guidance，with each dose of Qizhu Formula Granules taken orally for 12 weeks.The liver controlled attenuation parameter(CAP)，liver stiffness measurement(LSM)，body mass index(BMI)，glutamic pyruvic transaminase(GPT)，glutamic oxaloacetic transaminase(GOT) γ-glutamyl transferase(GGT)，total cholesterol(TC)，triglycerides(TG)，high-density lipoprotein cholesterol(HDL-C)，low-density lipoprotein cholesterol(LDL-C)，homeostatic model assessment for insulin resistance(HOMA-IR)，traditional Chinese medicine(TCM) efficacy index，and changes in serum metabolomics were compared before and after treatment in the observation group.Results:The comparison of clinical observation indexes revealed that after treatment，the observation group showed significant reductions in CAP，LSM，BMI，GPT，GOT，GGT，TC，and TG(P<0.05)，with increased HDL-C(P<0.05).No significant differences were observed in LDL-C and HOMA-IR.The total effective rate of the 31 patients was 93.55%.A total of 41 differential metabolites were identified in the control and observation groups before treatment.44 differential metabolites were identified before and after treatment in the observation group，among which the expression of 10 metabolites，such as stearic acid，was downregulated，and the expression of 22 metabolites，such as docosahexaenoic acid，was upregulated.Three main metabolic pathways were identified，including the synthesis of unsaturated fatty acids，the synthesis of primary bile acids，and porphyrin metabolism.Conclusion:Qizhu Formula effectively treats NAFLD patients with spleen deficiency and damp-heat syndrome by reducing hepatic fat deposition，regulating lipid metabolism，and improving liver function.Its mechanism is associated with modulating unsaturated fatty acid synthesis，primary bile acid synthesis，and porphyrin metabolism.