Objective：To discuss the significance of mammography and ultrasonography in breast cancer screening, and search of an appropriate method  for breast cancer screening.
Methods：A group of 387 women aged from 35 to 69 who were suspected to be an abnormal breast were chosen to undergo mammography,the positive diagnosis and uncertain cases then had ultrasonography, and the positive cases by ultrasonography underwent biopsy to confirm the diagnosis of breast cancer.
Results：Among the 387 cases, 83.22% of breasts contained more than 50% glands, 22 cases were positive and 75 cases were uncertain by mammography.The results of 22 positive cases were comfirmed by mammography and ultrasonography, and 3 cases among the 75 uncertain cases by mammogrophy were positive by ultrasonography. Biopsy was performed in 25 cases and 17 of them were confirmed to be breast cancer, while 2 cases of breast cancer had reached stage III. The sensitivity of mammography and ultrasonography was respectively 72.73% and 68.0%; there was no statistically significant differences（P＞0.05） between the 2 methods.
Conclusions：Most of the checked breasts in our series were dense, and mammography was not superior to ultrasonography in dense breasts.