Objective To explore the mechanism of action of Xiao chengqitang in the treatment of ulcerative colitis (UC) by network pharmacology. Methods From January 17th to January 20th, 2022, the active components and action targets of Xiao chengqitang (Radix Rhei Et Rhizome, Magnolia Officinalis Rehd Et Wils and Aurantii Fructus Immaturus) were obtained from Traditional Chinese Medicine System Pharmacology Database and Analysis Platform. “Ulcerative Colitis” was used as a search term to retrieve related targets of UC from GeneCards database, to obtain the targets for the treatment of UC using Xiao chengqitang. Then, Cytoscape 3.7.2 software was used for further topological analysis and the Chinese medicine compound-target network of genes was constructed. At the same time, protein-protein interaction network of Xiao chengqitang for the treatment of UC was constructed by STRING database. In addition, targets of Xiao chengqitang for the treatment of UC were applied for gene ontology (GO) analysis, as well as Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Results A total of 26 major active ingredients of Xiao chengqitang were obtained after screening, corresponding to 122 drug targets, 4837 disease targets for UC and 86 drug-disease common targets. According to protein-protein interaction network topology analysis parameters, 10 key therapeutic targets were screened, namely RAC-alpha serine/threonine-protein kinase, cellular tumor antigen p53, tumor necrosis factor-α, interleukin-6, caspase-3, prostaglandin-endoperoxidesynthases 2, transcription factor AP-1, vascular endothelial growth factor A, myc proto-oncogene protein and interleukin-1β. The results of GO and KEGG analysis indicated that the therapeutic targets of Xiao chengqitang for UC were mainly enriched in phosphatidylinositol 3-kinase-protein kinase B signaling pathway, inflammatory bowel disease, nuclear factor κB signaling pathway, calcium signaling pathway and peroxisome proliferators-activated receptor signaling pathway. Conclusions The potential mechanism of Xiao chengqitang in the treatment of UC may be that Xiao chengqitang acts on key therapeutic targets such as RAC-alpha serine/threonine-protein kinase, cellular tumor antigen p53, tumor necrosis factor-α, interleukin-6, prostaglandin-endoperoxidesynthases 2, vascular endothelial growth factor A and interleukin-1β, and participates in the regulation of phosphatidylinositol 3-kinase-protein kinase B signaling pathway, nuclear factor κB signaling pathway and calcium signaling pathway.