The common methods of breast examination include self-examination, clinical physical examination, mammography, ultrasound, CT, MRI, cytology, pathology, etc. Each of these methods has its own strengths and application space. Understanding the respective characteristics of these examination methods and applying a reasonable combination of multiple examination methods can obtain the necessary clinical diagnostic information with minimal time cost, economic cost, and physical trauma cost. Every woman should get into the habit of performing a self-examination once every menstrual cycle. Whenever possible, it is best to schedule the examination 3-5 days after menstruation, because at this time the volume of the breast is the smallest, the physiological breast swelling is the most complete, minor abnormalities of the breast are the easiest to detect, and the nature of the lesion is the easiest to judge accurately. Mammography is the most recognized method for early detection of breast cancer. Regular screening with this method can effectively reduce the death rate of breast cancer, and it is also an important tool for clinical examination of breast cancer, which can detect subclinical microscopic lesions. The most important feature is that it can be done in a very short time and obtain images that can be retained permanently, which can be easily observed and compared repeatedly. Mammography should be performed bilaterally, which facilitates comparative analysis and allows evaluation of whether the contralateral side also shows suspicious signs. The application of mammography’s stereotactic puncture biopsy equipment can also directly take biopsies of the lesion; for nipple overflow disease, contrast can be injected from the opening of the overflowing duct in the radiograph, which can show signs of duct expansion, occupancy, blockage and other signs to assist in the diagnosis, which is ductography. The advantage of ultrasound examination is that there is no radiological damage and it is suitable for all people, including pregnant, maternal and lactating women. It can perform multi-angle and repeated examinations of the breast, axilla, upper and lower clavicular area and other areas where breast cancer may recur or metastasize. Ultrasonography can also show the fine structure of the lesion and the relationship between the lesion and the surrounding tissues, and analyze the characteristics of the blood supply to the lesion. Distinguishing the cystic and solid nature of the lesion is an outstanding advantage of ultrasound examination. Ultrasound-guided puncture biopsy has become the most valuable means to confirm the diagnosis because of the accuracy, safety and convenience of material extraction. CT, MRI, PET, radionuclide whole-body bone scan MRI is basically unaffected by the density of the breast, and its sensitivity in detecting occult lesions may be better than that of mammography and ultrasound, especially in young women with dense breasts. The disadvantage is that it is economically costly and not suitable for repeated use and screening. Evaluation of skeletal, cranial, thoracic, abdominal, and pelvic metastases with PET, CT, and radionuclides. These screening methods are often combined in breast disease, each with room for application. Ductal endoscopy Breast ductal endoscopy is a new examination method developed in recent years, which can be used for direct observation of nipple overflow disease, sampling biopsy and auxiliary treatment. Pathological examination Whether it is clinical examination or various imaging examinations, the results cannot be used as the final basis to confirm the diagnosis of breast cancer, no matter how typical and certain these examinations are, only the results of caseological examination are the final basis for diagnosis. Non-surgical sampling for pathology and cytology is becoming widely accepted. These measures in conjunction with rational and comprehensive treatment bring many practical benefits to patients.