In order to explore the combination patterns and potential molecular mechanisms of Paeonia lactiflora in treating PMOP (postmenopausal osteoporosis) from the pathogenesis perspective of “insufficient liver substance and excessive liver function” in postmenopausal women. Excel 2023 was used to organise relevant prescriptions from the Chinese Patent Database. The standardised prescriptions were then analysed for four properties, five flavours, meridian tropism, association rules, and clustering. Network pharmacology and molecular docking methods were also employed to investigate the molecular mechanisms. The results show that among the 107 prescriptions included, Paeonia lactiflora is frequently combined with Angelica sinensis, Rehmannia glutinosa, Astragalus membranaceus, Achyranthes bidentata, Glycyrrhiza uralensis, Ligusticum chuanxiong, Epimedium sagittatum, Eucommia ulmoides, and Drynaria fortunei, among others. The predominant properties are cold, warm, and neutral, while the predominant flavours are pungent, sweet, and bitter, with most herbs attributed to the liver, kidney, and lung meridians. The core combinations include Paeonia lactiflora-Angelica sinensis and Paeonia lactiflora-Rehmannia glutinosa. Other constituents in core prescriptions containing Paeonia lactiflora are Atractylodes macrocephala, Psoralea corylifolia, Cibotium barometz, and Ligustrum lucidum. A total of 37 intersecting targets between Paeonia lactiflora and PMOP are identified via network pharmacology. PPI(protein-protein interaction) analysis reveales core targets including ALB, AKT1, ESR1, PPARG, and EGFR, involving pathways such as the oestrogen receptor pathway, FoxO signalling pathway, and MAPK signalling pathway. Molecular docking indicates favourable binding activity between the core targets and drug components. It is concluded that Paeonia lactiflora (white peony root) exhibits the effects of ‘nourishing blood and softening the liver, consolidating yin and harmonising hyperactivity’, which align with the pathogenesis of PMOP characterised by ‘insufficient liver substance and excessive liver function’. Paeonia lactiflora may mediate targets including ALB, AKT1, ESR1, PPARG, and EGFR, thereby exerting effects on improving bone metabolic balance through multiple pathways such as the oestrogen receptor pathway.