CIN3 is usually still within the epithelial tissue. CIN3 is one of the results of cervical biopsy, which indicates that the cells have lesions, but are still confined to the epithelium and have not progressed downward, which belongs to the high-level epithelial lesions in the cervical area, that is, a part of the pre-cancerous lesions of cervical cancer, and requires timely targeted treatment, or else it may evolve into cervical cancer. Clinically, CIN3 is mainly treated by cervical conization surgery, which is a hammer-shaped excision of the cervix, and pathological examination is conducted after the surgery to determine the situation and help formulate further treatment plan. Patients are advised to undergo regular review after treatment to dynamically observe the progress of the disease so as to intervene in the treatment as early as possible.