Objective:To assess the effectiveness of Yishen Jiangu Granules(益肾健骨颗粒, YSJGG)on aromatase inhibitor-associated musculoskeletal symptoms (AIMSS).Methods:A single-arm,open-label study was conducted in 34 postmenopausal women with breast cancer who experienced AIMSS.Patients were treated with YSJGG for 12 weeks (12.4 g orally twice daily).The primary outcome was a change in the mean worst pain score of Brief Pain Inventory-Short Form (BPI-SF) over 12 weeks,and the second outcomes included changes in pain severity and pain-related interference of BPI-SF and Westem Ontario and McMaster Universities Osteoarthritis Index (WOMAC),Modified Score for the Assessment of Chronic Rheumatoid Affections of the Hands (M-SACRAH),the Functional Assessment of Cancer Therapy-Breast (FACT-B),bone mineral density (BMD) and blood indices such as calcium (Ca),phosphate (P),and alkaline phosphatase (ALP).Results:Of 37 women recruited,30 initiated the therapy and 24 were evaluable at 12 weeks.The primary outcome (BPI-SF worst pain scores) achieved a 2.17-point reduction compared with baseline (5.75 ± 1.87 vs 3.58 ± 2.15,P＜0.01).There were reductions in pain severity (decreased 1.65,P＜0.01) and pain-related interference (decreased 2.55,P＜0.01).The changes in WOMAC and M-SACRAH scores were similar to BPI-SF (P＜0.05).In the FACT-B,only physical well.being and functional well-being were improved compared with baseline (P＜0.05).No clinical differences were found in BMD,Ca,P and ALP.Conclusion:YSJGG is an effective and well-tolerated agent to reduce AIMSS.