Abstract: We used network pharmacology to predict the mechanism in the treatment of rheumatoid arthritis (RA) via modified Gan Cao Fu Zi Decoction (GCFZ), and validated the results of the analysis and explored the pharmacodynamic effects of GCFZ through animal experiments. Firstly, TCMID, SymMap, HERB, STITCH and GEO databases were utilized to obtain the target genes of GCFZ for the treatment of RA, which yielded a total of 1 250 differentially expressed genes for RA, 534 genes for GCFZ targets and 83 intersecting genes. Then functional enrichment analysis of the intersecting genes was performed through GO and KEGG databases, and the results revealed that GCFZ and its active ingredients mainly functioned through cytokine pathways, where chemokine signaling pathway and tumor necrosis factor (TNF) signaling pathway were enriched with a high number of genes. Cytoscape 3.8.0 software was used to construct the drug-target-disease network and screen key proteins, which included TNF, C-X-C chemokine ligand 8 (CXCL8), C-X-C chemokine ligand 10 (CXCL10), C-C chemokine ligand 5 (CCL5), C-X-C chemokine ligand 2 (CXCL2) and C-X-C chemokine receptor type 4 (CXCR4). The molecular docking technology was used to confirm the binding ability of the main active ingredients of GCFZ to the core proteins. Additionally, the therapeutic effects of GCFZ in low (4 g·kg^-1), medium (8 g·kg^-1) and high (16 g·kg^-1) dose groups were investigated by constructing the collagen-induced arthritis (CIA) rat model. X-ray imaging approach, HE staining and Safranin O-Fast Green staining showed that GCFZ treatment significantly improved bone destruction, synovial hyperplasia and cartilage damage in CIA rats, while immunofluorescence results showed that GCFZ treatment could regulate the expression of TNF, CXCL8 and CCL5. In summary, our results indicate that GCFZ contains a variety of small molecule pharmacodynamic substances, which can exert therapeutic effects via multiple targets and pathways, and obviously reduce the symptoms of arthritis in CIA rats. This animal experiment of our research was approved by the Experimental Animal Management and Ethics Committee of Bengbu Medical College.