To observe the effects of thunder-fire moxibustion on the balance function and musculoskeletal metabolism in female patients of primary osteoporosis (POP) with low muscle mass. Sixty female patients of POP with low muscle mass were randomly divided into an observation group (30 cases, 5 cases dropped out) and a control group (30 cases, 2 cases dropped out). The patients in the control group were treated with oral administration of Caltrate D (1.5 g calcium carbonate + 125 IU vitamin D3), one tablet per day for 12 weeks. In addition to the control treatment, the patients in the observation group were treated with thunder-fire moxibustion at Mingmen (GV 4), Yaoyangguan (GV 3), bilateral Ganshu (BL 18), Shenshu (BL 23), and Dachangshu (BL 25), 30 min per acupoint, once every other day, three times a week, for 12 weeks. Balance function indexes (95% confidence ellipse area of the center of pressure [COP], total displacement, average speed), lumbar pain visual analogue scale (VAS), serum muscle metabolism factors (myostatin [MSTN], peroxisome proliferator-activated receptor γ coactivator-1α [PGC-1α]) and bone metabolism factors (aminoterminal propeptide typeⅠ procollagen [PINP], C-terminal telopeptide of typeⅠcollagen [CTX-Ⅰ]) were compared before and after treatment in both groups. Compared before treatment, the 95% confidence ellipse area of COP, total displacement, and average speed in the observation group were decreased after treatment (P<0.01), and the above indexes in the observation group were lower than those in the control group (P<0.05). Compared before treatment, the VAS scores in both groups were decreased after treatment (P<0.01), the score in the observation group was lower than that in the control group (P<0.01). Compared before treatment, the serum levels of MSTN, PINP and CTX-Ⅰ in the observation group were reduced after treatment (P<0.01), while the serum level of PGC-1α was increased (P<0.01). The control group showed a decrease in serum level of MSTN (P<0.05). The observation group had lower serum levels of MSTN and PINP (P<0.05) and higher serum level of PGC-1α (P<0.01) compared to the control group. The thunder-fire moxibustion can effectively relieve lumbar pain, improve balance function, and regulate musculoskeletal metabolism in female patients of POP with low muscle mass.