Currently, mammography and ultrasound are recognized as the most common and effective clinical aids for breast screening. Mammography, also known as mammography, is the first and easiest, most reliable non-invasive means of diagnosing breast disease, with relatively little pain, ease of use, high resolution, good repeatability, and images that can be compared before and after, regardless of age and body shape. Especially for large breasts and fatty breasts, its diagnostic accuracy can be as high as 95%. For stage T0 breast cancer (negative clinical diagnosis), which has a few tiny calcifications as its only manifestation, it can only be detected and diagnosed at an early stage by soft X-ray examination, with a diagnostic sensitivity of 82%-89% and specificity of 87%-94%. Mammography can often detect nodules that cannot be reached by physicians, the so-called “occult breast cancer” and very early carcinoma in situ, and can detect early breast cancer two years earlier than experienced physicians. The radiation dose is also reduced to less than 0.003Gy per person (four positions on both sides), usually once a year, which is a contrast and not harmful to the human body. Even when the clinical diagnosis of breast cancer is clear, mammography should still be performed because it can help clarify the location of the tumor, the extent of tumor infiltration, the presence of multiple foci and the condition of the contralateral breast, which are essential for proper treatment planning.