Breast BI-RADS classification is a commonly recognized method of imaging classification of breast diseases, which may be classified into grades 0-6 according to the degree of malignancy of the disease. Grade 0: Incomplete information, need to be reassessed in conjunction with other examinations. Grade 1: Negative, no obvious abnormality seen, routine physical examination (once a year) is recommended. Grade 2: Benign lesions, including simple breast cysts, unchanged fibroadenomas, etc. Regular follow-up is recommended (once every 6 months~1 year). Grade 3: Benign possibilities, round or oval solid lumps with smooth edges are seen, which may be fibroadenomas or complex breast cysts. Short-term follow-up (every 3~6 months) is recommended, and no change in condition in 2 years of follow-up can be downgraded to grade 2. Grade 4: suspected malignancy, categorized as 4a, 4b, 4c. 4a is low suspected malignancy (≤10%), 4b is moderate suspected malignancy (≤50%), and 4c is highly suspected malignancy (≤95%), which usually requires a biopsy or puncture cytology for definitive diagnosis. Grade 5: highly suspicious for malignancy (≥95%) clinically almost certainly malignant, with characteristic abnormalities on ultrasound, definitive treatment should be initiated. Grade 6: Biopsy confirmed malignancy. Clinical appropriate measures need to be taken for active treatment. If there is any discomfort, consult a doctor promptly and follow the medical advice.