Third-degree cervical erosion in women is a clinical manifestation of cervical erosion caused by the lateral displacement of the columnar epithelium in place of the squamous epithelium in the female cervix. If the immune system of the patient is low in this case, when attacked by pathogens such as bacteria, mycoplasma, chlamydia and viruses, it can cause localized cervicitis, which can lead to an increase in the degree of cervical erosion, and some patients can show symptoms of third degree cervical erosion. Clinically, the patient may have yellowish discharge, sometimes with yellow-purulent changes, increased discharge and an unpleasant odor. If the patient has this condition, he/she should go to a public hospital for HPV test, laboratory examination of the secretions and colposcopy for a clear diagnosis and treatment according to the test results.