BACKGROUND: The frequently occurred chemotherapy-induced diarrhea (CID) caused by irinotecan (CPT-11) administration has been the most representative side-effects of CPT-11, resulting in the chemotherapy suspension or failure. Our previous studies indicated that Gegen Qinlian formula exhibited a significant alleviation effect on CPT-11-induced diarrhea. However, referencing to Japanese Kampo medicine, the TCM standard decoction would supply the gap between ancient preparation application and modern industrial production. METHODS: The LC-MS technology combined with network pharmacology was employed to identify the active ingredients and mechanisms of GQD standard decoction for CPT-11-induced diarrhea. The anti-inflammatory activities associated with intestinal barrier function of GQD standard decoction were studied by SN-38 activated NCM460 cells in vitro and CPT-11-induced diarrhea in vivo. Proteins involved in inflammation, mRNA levels, disease severity scores, and histology involved in intestinal inflammation were analysed. RESULTS: There were 37 active compounds were identified in GQD standard decoction. Network pharmacology analyses indicated that PI3K-AKT signaling pathway were probably the main pathway of GQD standard decoction in CPT-11-induced diarrhea treatment, and PIK3R1, AKT1, NF-κB1 were the core proteins. Moreover, we found that the key proteins and pathway predicted above was verified in vivo and in vitro experiments, and the GQD standard decoction could protect the cellular proliferation in vitro and ameliorate CPT-11-induced diarrhea in mice model. CONCLUSIONS: This study demonstrated the molecular mechanism of 37 active ingredients in GQD standard decoction against CPT-11-induced diarrhea. And the core proteins and pathway were validated by experiment. This data establishes the groundwork for particular molecular mechanism of GQD standard decoction active components, and this research can provide a scientific reference for the TCM therapy of CID.