Objective To study the relationship between knee osteoarthritis progression and the ration of fat,lean,or bone mineral content(BMC).Methods 36 joints of knee with osteoarthritis in 31 women were divided into two groups according to the knee joint space,joint space narrowing group and non-narrowing group.The body mass index(BMI)was calculated.The X-ray(weight bearing)of knee joint was taken.The fat,lean,BMC and mass of leg were detected with the dual energy X-ray absorptiometry(DXA).Results There was no distinct difference between sides and age distribution for the tested groups(P>0.05).The BMI and fat/mass ratio of leg in the joint space narrowing group were obviously higher than that of the non-narrowing group(P<0.05),while the lean/mass ratio of leg in the joint space narrowing group was distinctly lower than that of the non-narrowing group(P<0.05).Conclusion The deterioration of the female knee osteoarthritis can be mainly attributed to the increase of the BMI and fat/mass ratio as well as the decrease of the lean/mass ratio of leg.