Endometrial cancer should refer to endometrial cancer, the thickness of the endometrium usually reaches 10mm and may even reach 20mm, but not all endometrial thickening is caused by endometrial cancer. Endometrial cancer is a group of epithelial malignant tumors occurring in the endometrium. Due to the malignant proliferation of the endometrium, the manifestation of endometrial thickening can be found in ultrasound, pelvic MRI and other examinations of the patients with this disease, and this disease can also lead to the symptoms of vaginal bleeding, abnormal vaginal fluid, abdominal pain, anemia, and emaciation. Usually for premenopausal women, the thickness of the endometrium is about 5~12mm is normal, for postmenopausal women, the thickness of the endometrium is less than 5mm is normal, and if the thickness of the endometrium reaches 10~20mm, or even thicker, then we need to be vigilant. Apart from endometrial cancer, endometrial hyperplasia, endometrial polyps and other diseases can also cause endometrial thickening. If endometrial thickening is detected during examination, please follow the doctor’s advice to improve the relevant examination and treatment.