Post-menopausal osteoporosis women are at increased risk for skeletal fractures with higher mortality and lower quality of life. Some studies have reported fall risk reduction in the elderly after Tai chi practice. Tai chi is a weight bearing mind-body exercise that has been reported to positively influence bone mineral density and improve postural control in different pathologies. The aim of this observational randomized case control study is to evaluate the effect of Tai chi on balance and quality of life in postmenopausal women with osteoporosis. A total of 98 postmenopausal osteoporosis women, aged 70.6±8.2 years (mean and standard deviation), (mean T-score of the hip and spine were-2.9± 0.92 and -2.8±1.08), have been recruited in outpatients University Physical Medicine and Rehabilitation Hospital between June 2016 and September 2018. They have been randomized to a Tai group (56 patients, mean age 71.61±7.97 years) practiced 6-month Tai chi program, two times week, plus standard care or to a Control Group (42 patients, mean age 69.71±8.61 years) practiced usual care. Patients with oncological, neurological, cognitive, vestibular and visual diseases were excluded. Patients were evaluated at baseline (T0), prior Tai chi and after 6 month (T1) with 36-Item Short Form Health Survey (SF-36), and a stabilometric-standardized exam performed for the evaluation, respectively, of the quality of life and the static balance. The groups were homogenous at baseline. T1 evaluation showed better results in Tai chi group, in SF36 Physical functioning (p level: 0.021), Physical health pain (p level: 0.020), Physical composite score (p level: 0.003) scores, compared with control group. There were not significant differences between groups in stabilometric analysis. Tai chi group showed significant better stabilometric values at T1 compared with T0 in mean anterior-posterior (p level: 0.001) and medio-lateral (p level: 0.019) velocity, in perimeter (p level 0.001) , and in the area of the ellipse ( p level 0.006) in a within group analysis. Tai chi seemed to be effective in improving physical aspects of quality of life, in postmenopausal women with osteoporosis. Standing balance seems to increase after 6 months Tai chi program, in post-menopausal also if results were not significant. Further studies will be useful to measure effects of a Tai chi longer practice, as literature suggests, and a possible reduction of falling risk and fractures.