Solid nodules in the breast are mainly seen in breast hyperplasia, breast fibroma, breast lipoma, breast cancer, etc. It is necessary to improve the auxiliary examinations in order to clarify the etiology. 1. Breast hyperplasia: it is mainly related to endocrine disorders in the patient’s body, especially the elevation of estrogen, which will lead to solid hyperplasia of breast glands. 2. Breast fibroma: it is a benign tumor of the breast, which is also related to estrogen stimulation, mostly solitary, round or oval, with clear boundary. There is no pain or discomfort, and color ultrasound is helpful for diagnosis. 3. Breast lipoma: mostly related to endocrine disorders, obesity and high-fat diet, etc. It is painless and soft lump. 4. Breast cancer: it is a painless and progressively enlarged lump, hard and not clearly demarcated from the surrounding tissues. Patients may have malignant manifestations such as emaciation, fatigue and anemia. There are also inflammatory nodules in the breast and other causes such as trauma, and it is recommended to go to the hospital to improve the auxiliary examinations, to clarify the nature of the lumps, and to give the appropriate treatment by professional physicians for the condition.