Cervical cancer occupies the first place among female reproductive system tumors, and its incidence and mortality rate are second only to breast cancer, which seriously threatens women’s physical and mental health. Early detection of cervical precancerous lesions and early diagnosis of cervical cancer are the key factors to improve the cure rate, survival rate and reduce the incidence of cervical cancer. Numerous epidemiological studies have confirmed that human papillomavirus (HPV) infection is an important environmental factor in the occurrence and development of cervical cancer. It has been found that it takes approximately 10 years for CIN to develop into cervical cancer, so effective intervention during the development process is of great importance to reduce the incidence of cervical cancer. Cervical cancer is mainly screened through a “three-step” screening process: first step: cervical cytology – Pap smear or liquid-based cytology (TCT); second step: colposcopy; third step: cervical biopsy. Cervical liquid-based thin-layer cytology is the basic method for CIN and early cervical cancer screening and a necessary step for diagnosis. Start time: Screening should be started 3 years after the start of sexual intercourse, or after the age of 21, and be reviewed regularly. Precautions: Do not put pills in the vagina 72 hours before the test. Of course, if there is abnormal vaginal bleeding, the test should be done promptly.