This study aims to investigate the mechanism by which notopterol promotes osteoblast differentiation using network pharmacology and in vitro experiments. The potential targets of notopterol were predicted using databases including PubChem and SwissTargetPrediction. Disease targets related to osteoporosis were retrieved from the GeneCards, OMIM, and CTD databases. The Venny, STRING, and Cytoscape tools were utilized to construct a drug-disease common target network and to perform GO functional enrichment and KEGG pathway enrichment analyses. Mouse calvarial preosteoblast subclone 14 (MC3T3-E1) cell and mouse bone marrow mesenchymal stem cell were used as models. The safe concentration range of notopterol was determined using CCK-8 assay. The osteogenic differentiation-promoting effects and underlying mechanisms were evaluated by assessing alkaline phosphatase (ALP) activity, Alizarin Red S staining, RT-qPCR, Western blot, and validation using the wingless-type MMTV integration site family/beta-catenin (WNT/β-catenin) signaling pathway inhibitor XAV-939. The results showed that network pharmacology screening identified 61 common targets between notopterol and osteoporosis. Core targets included prostaglandin-endoperoxide synthase 2 (PTGS2) (which encodes the cyclooxygenase-2 (COX2) protein), potassium voltage-gated channel subfamily A member 2 (KCNA2), and hypoxia inducible factor 1 subunit alpha (HIF1A). KEGG analysis suggested a potential role through the WNT/β-catenin signaling pathway. Molecular docking indicated that notopterol exhibited the most stable binding with the COX2 protein (binding energy: -8.5 kcal/mol). In vitro experiments confirmed that at safe concentrations (5, 10, 20 μmol/L), notopterol significantly enhanced ALP activity, promoted calcium nodule formation, and upregulated the mRNA expression of osteogenic-related genes Runt-related transcription factor 2 (Runx2), transcription factor Sp7 (Sp7), and distal-less homeobox 5 (Dlx5). Western blot analysis further demonstrated that notopterol activates the WNT/β-catenin pathway by upregulating COX2 expression, promoting β-catenin nuclear translocation and the expression of downstream proteins G1/S-specific cyclin-D1 (Cyclin D1) and B-cell lymphoma 2 (BCL-2). These effects were reversed by XAV-939. The findings suggest that notopterol promotes osteoblast differentiation potentially by regulating the COX2/WNT/β-catenin signaling axis, providing a theoretical basis for the application of notopterol in the treatment of osteoporosis.