To explore the anti-inflammatory mechanism of psoralen(PSO) in the treatment of osteoarthritis(OA) through network pharmacology combined with experimental validation.Methods:SymMap2.0 and other drug databases were searched for the targets of PSO.The genes of OA were retrieved from GeneCards.The common targets shared by PSO and OA were submitted to String to build the protein-protein interaction(PPI) network.The Cytoscape plug-in was used for the pathway analysis of the core targets.Metascape was used for the enrichment analysis.The herbs and orthopedic diseases involving PSO compounds，the traditional Chinese medicine(TCM) syndromes and the modern medical symptoms and syndromes treated by PSO，and the TCM syndromes and modern medical symptoms and syndromes of OA were downloaded，and a compound-herb-symptom/syndrome diagram was established for the treatment of OA with PSO.Furthermore，transwell systems of diseased cartilage-synovial cells were established and randomized into low-，medium-，and high-dose(1，8，and 50 μmol/L) PSO and blank control groups.Quantitative real-time PCR(qPCR) was employed to measure the messenger RNA(mRNA) levels and verify the predicted results.Results:The screening yielded 27 targets of PSO and 741 targets of OA.Sixteen common targets were predicted to be involved in the treatment of OA with PSO and submitted to the String，in which the PPI network was established，involving a total of 15 nodes and 46 edges.The results of enrichment analysis showed that the compounds mainly acted on the collagen-containing extracellular matrix，and PSO could improve the synovial fluid-cartilage interaction and regulate bone metabolism in the inflammatory microenvironment of the joint.The targets were mainly enriched in osteoclast differentiation and interleukin-17(IL-17) pathways.There were 21 terms of PSO-containing drugs and 14 terms of PSO-related orthopedic diseases in the SymMap.Six common TCM syndromes and 1 common modern medical syndrome were shared by PSO and OA，and a compound-herb-symptom/syndrome diagram with 71 nodes and 78 edges was established.The experimental results showed that compared with the blank control group，low-dose PSO elevated the levels of nuclear factor kappa-B(NF-κB) and IL-17(P<0.01); medium-dose PSO lowered the levels of tumor necrosis factor-α(TNF-α)，NF-κB，and IL-17(P<0.01); and high-dose PSO did not cause significant changes.Conclusion:The literature review and experiments of protein interactions verified that PSO played a positive role in inhibiting the inflammatory response of OA and improving the cartilage-synovial cell interaction.