Colposcopy is valuable in the diagnosis of diseases of the lower female genital tract, especially in the diagnosis of cervical disease. The steps of colposcopy are as follows: first, after confirming that the patient has no contraindications to colposcopy, the patient is placed in a cystotomy position, the cervicovaginal area is fully exposed with a vaginal speculum and a cotton ball is used to gently wipe away cervical secretions. At a distance of about 20 cm from the vaginal opening or genitalia, the colposcope lens is aimed at the cervix or the area to be observed. The colposcope is opened and the focal length is adjusted, usually starting with a 10x low magnification lens for cursory observation of the area to be examined, such as cervical shape, color and vascularity. The epithelium is then purified and swollen by rubbing the vaginal part of the cervix with 3% acetic acid cotton balls, which allows for a clearer observation of the lesion’s border and surface morphology. Finally, an iodine test is performed with a compound iodine solution, and a biopsy is taken from the negative iodine test area or the suspected lesion and sent for pathological examination. The purpose of colposcopy is to observe, through magnification, small lesions in the vaginal part of the cervix that are invisible to the naked eye, and to provide biopsies of suspicious abnormal areas for diagnosis in combination with pathological examination, thus improving the diagnosis rate of cervical precancer and cervical cancer.