Objective. Ulcerative colitis is an intestinal condition that severely affects the life quality of a patient. Jiawei Zhengqi powder (JWZQS) has some therapeutic benefits for ulcerative colitis. The current study investigated the therapeutic mechanism of JWZQS for ulcerative colitis using a network pharmacology analytical approach. Methods. In this study, network pharmacology was used to investigate the potential mechanism of JWZQS in treating ulcerative colitis. The common targets between the two were identified, and a network map was created with the Cytoscape software. The Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analyses of JWZQS was performed using the Metascape database. Protein-protein interaction networks (PPI) was created to screen core targets and main components, and molecular docking was conducted between the main components and core targets. The expression levels of IL-1β, IL-6, and TNF-α were detected in animal experiments. Their effect on the NF-κB signaling pathway and the protective mechanism of JWZQS on the colon by tight junction protein were investigated. Results. There were 2127 potential ulcerative colitis targets and 35 components identified, including 201 non-reproducible targets and 123 targets shared by drugs and diseases. Following the analysis, we discovered 13 significant active components and 10 core targets. The first 5 active ingredients and their corresponding targets were molecularly docked, and the results showed a high level of affinity. GO analysis showed that JWZQS participate in multiple biological processes to treat UC. KEGG analysis showed that JWZQS may be involved in regulating multiple pathways, and the NF-κB signaling pathway was selected for analysis and verification. JWZQS has been shown in animal studies to effectively inhibit the NF-κB pathway; reduce the expression of IL-1β, TNF-α, and IL-6 in colon tissue; and increase the expression of ZO-1, Occludin, and Claudin-1. Conclusion. The network pharmacological study provides preliminary evidence that JWZQS can treat UC through multiple components and targets. JWZQS has been shown in animal studies to effectively reduce the expression levels of IL-1β, TNF-α, and IL-6, inhibit the phosphorylation of the NF-κB pathway, and alleviate colon injury. JWZQS can be used in clinical, but the precise mechanism of UC treatment requires further investigation.