Objective To study the rule of“treating different diseases with the same method”in traditional Chinese medicine treatment of femoral head necrosis（ONFH）and osteoporosis（OP）using data mining technology. Methods We searched Chinese Na-tional Knowledge Infrastructure，the database of prescription modern application，and the Chinese prescription database for clinical re-search on using traditional Chinese medicine for treating femoral head necrosis and osteoporosis，and constructed a database for analy-sis. We performed an association rule analysis based on the Apriori algorithm，then a cluster analysis using SPSS，and subsequently，net-work pharmacology analysis for the potential mechanism of high-frequency drug combinations in treating the two diseases was used. Results Sixty-four prescriptions for ONFH and 69 prescriptions for OP were screened out. Angelica sinensis was the most frequently used single medicine for both ONFH and OP. The high-frequency single medicines for ONFH included Radix Achyranthis Bidentatae， Rhizoma Chuanxiong，Carthamus tinctorius，Dipsacus japonicus，and Astragalus propinquus. The high-frequency single medicines for OP included prepared Radix Rehmanniae，Eucommia ulmoides，Herba Epimedii，and Radix Glycyrrhizae. Most of the commonly used medicines for the two diseases belonged to the drugs tonifying deficiency，promoting blood circulation，and dredging collaterals. The most commonly used drug pairs were A. sinensis-Codonopsis pilosula and A. sinensis-Radix Paeoniae Alba. The cluster analysis ob-tained four core combinations each for ONFH and OP，two of which were suitable for both diseases and the other two combinations were unique to the corresponding diseases. The mechanism analysis of the high-frequency drug pairs showed that 4 components，7 key tar-gets，and 10 pathways in the drug pair of A. sinensis-Radix Paeoniae Alba could act in both diseases. Conclusion The concept of “treating different diseases with the same method”in the treatment of ONFH and OP is reflected by the results that both conditions are commonly treated with deficiency-tonifying drugs and blood-activating and stasis-resolving drugs and share some key targets and sig-naling pathways. In addition，Rhizoma Drynariae and Radix Achyranthis Bidentatae are also frequently used for ONFH to adjust Yin and Yang，while prepared Radix Rehmanniae，A. propinquus，and Dioscorea opposita are used for OP to benefit qi and nourish yin，re-flecting the difference in pathogenesis of the two diseases，which provides a basis for the treatment of the two diseases.