Clinicians generally use physical examination (looking, smelling, asking, and cutting) to make a preliminary diagnosis of breast disease. For instrumental examinations, mammography and color multispectral ultrasound are currently recognized as the most effective and easy-to-implement methods for clinical examination of breast disease, especially for screening of breast cancer. Other methods include ductoscopy, pathology and infrared breast examinations. The advantages of mammography and color multispectral ultrasound and their scope of application are as follows: Advantages of breast ultrasound diagnosis: 1. 2.Identify the nature of the mass. (The value of identifying cystic or solid breast masses is greater) 3. Which layer has the lesion, can be localized from the ultrasound image. Ultrasound can help to exclude tumors when X-ray shows dense mammary glands. For axillary and supraclavicular lymph node metastases, ultrasound can indicate the presence or absence of lymph node enlargement. Advantages of X-ray breast diagnosis: 1.For breast cancer less than 1cm, ultrasound often shows unclear, but X-ray can detect it. Ultrasound can not easily show the particle-like calcification points or burr-like structures on mammogram, but X-ray can detect and make diagnosis. Therefore, ultrasound and X-ray examination of the breast, due to the different imaging principles and information obtained, each has its own strengths and should be used individually or in combination in order to improve the level of diagnosis of breast lesions.