The number of patients suffering from osteoporosis increases year by year. Osteoporosis is characterized by decreased bone density and increases the risk of fracture. The femoral neck is the most possible part of the fracture. In this study, bone strength of ovariectomized osteopenia (OVX) model mouse was measured using a newly improved stage device for femoral neck fracture. METHODS Female ICR mice were divided into the sham and OVX groups. Eight weeks after surgery, right and left femurs were taken out. The right femur neck was set on a bone strength tester and the maximum breaking load (N) was measured. The left femur was measured for bone density using a CT. All results were regression analyzed with Stat View analysis software and their correlation was obtained. RESULTS In the right femur, N value of the OVX group showed a significant decrease compared to that of the sham group. The value of bone density of OVX group was also lower. Regression analysis of N value and bone density revealed a significant positive correlation coefficient in total bone density and cancellous bone density. CONCLUSION The present study indicates that the novel strength test of the femoral neck using the femoral neck fracture stage is useful for an evaluation of OVX model mice.