Acetic acid white epithelium is a term used for colposcopy, which means that during colposcopy, acetic acid needs to be placed in the cervix and vagina, and after 1 minute, the color change of the cervix and vagina is observed. If white epithelium is seen, it means that there are precancerous lesions of the cervix, and the severity can be observed through the white epithelium, which can be divided into mild lesions and severe lesions. Biopsies are taken from the vinegar white epithelium for pathology and the next step of treatment is determined according to the results of the pathology, so the acetic acid test must be used during all colposcopy.