Objective: To explore the specific pharmacological molecular mechanisms of Kai Xin San (KXS) on treating Alzheimer's disease (AD) based on network pharmacology and experimental validation. Methods: The chemical compounds of KXS and their corresponding targets were screened using the Encyclopedia of Traditional Chinese Medicine (ETCM) database. AD-related target proteins were obtained from MalaCards database and DisGeNET databases. Key compounds and targets were identified from the compound-target-disease network and protein-protein interaction (PPI) network analysis. Functional enrichment analysis predicted the potential key signaling pathways involved in the treatment of AD with KXS. The binding affinities between key ingredients and targets were further verified using molecular docking. Finally, the predicted key signaling pathway was validated experimentally. Positioning navigation and space search experiments were conducted to evaluate the cognitive improvement effect of KXS on AD rats. Western blot was used to further examine and investigate the expression of the key target proteins related to the predicted pathway. Results: In total, 38 active compounds and 469 corresponding targets of KXS were screened, and 264 target proteins associated with AD were identified. The compound-target-disease and PPI networks identified key active ingredients and protein targets. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested a potential effect of KXS in the treatment of AD via the amyloid beta (A beta)-glycogen synthase kinase-3 beta (GSK3 beta)-Tau pathway. Molecular docking revealed a high binding affinity between the key ingredients and targets. In vivo, KXS treatment significantly improved cognitive deficits in AD rats induced by A beta(1-42), decreased the levels of A beta, p-GSK3 beta, p-Tau and cyclin-dependent kinase 5, and increased the expressions of protein phosphatase 1 alpha (PP1A) and PP2A (PP < 0.01). Conclusion: KXS exerted neuroprotective effects by regulating the A beta -GSK3 beta-Tau signaling pathway, which provides novel insights into the therapeutic mechanism of KXS and a feasible pharmacological strategy for the treatment of AD.