Objective: To investigate the effect of square dance on bone mineral density and osphyarthrosis and gonitis in postmenopausal women. Methods: The postmenopausal women who danced on a square in the Second Hospital of Wuxi Affiliated to Nanjing Medical University from January 2014 to January 2015 were selected and divided into different groups by age.Each group of subjects received the bone mineral density test of their lumbar vertebral body 1-3, so as to analyze the difference between the bone mineral density of each vertebral body and the corresponding age, as well as the relationship between the age and the bone mineral density.The bone mineral density of their lumbar vertebrae was measured one year later, and the incidence rates of osphyarthrosis and gonitis were observed, thus the influence of square dancing on bone mineral density and the incidence of osphyarthrosis and gonitis of postmenopausal women was studied. Results: There was statistically significant difference in the bone mineral density for lumbar vertebrae of different age groups(F=74.213, P<0.01), among which the bone mineral density of lumbar vertebrae 1~3 in the age group of 45-60 showed a decreasing trend, with a medium negative correlation with age(r=0.978). After dancing on a square for 1 year, the bone mineral density of lumbar vertebral body 1-3 of subjects in the age group of 45-50, the age group of >50-55, the age group of >55~60, the age group of >60-65, the age group of >65-70 and the age group of over 70 were (149.51±31.65)mg/cm³, (118.98±34.55)mg/cm³, (103.56±23.44)mg/cm³, (86.88±34.21)mg/cm³, (69.89±29.72)mg/cm³, (61.22±34.21)mg/cm³, respectively, which increased slightly; the bone mineral density of the age group of 45-50, the age group of >50-55 and the age group of >55-60 increased significantly(F=8.012, 3.567, 4.774, all P<0.05). Square dancing had no significant effect on the incidence of osphyarthrosis and gonitis of postmenopausal women. Conclusion The age group of 45-60 is the most obvious period of bone mineral density decline for women.Square dancing can effectively improve the bone mineral density of postmenopausal women in this age group, but has no obvious effect on the improvement of the bone mineral density of women in other age groups.Square dancing has no effect on the incidence of osphyarthrosis and gonitis of postmenopausal women.