CT can examine the pelvis. Most of the pelvis are substantial organs, and lesions in substantial organs can be detected by CT, such as uterine fibroids, cervical cancer, endometrial cancer, ovarian cysts, ovarian cancer, or pelvic peritoneal primary cancer, peritoneal mesothelioma and other malignant tumors. Pelvic CT has certain diagnostic value for bladder, rectum, and retroperitoneal masses. CT examination can clearly know the size, density, morphology of the tumor or lesion and its relationship with neighboring structures, which is very necessary for preoperative surgery to give clear guidance for surgery, and it can also make a diagnosis of whether there is any invasion of the surrounding structures. Pelvic CT is a part of whole body imaging examination. For suspected malignant tumors, not only pelvic CT examination, but also abdominal and thoracic imaging examination should be done. Therefore, CT examination, including CT-enhanced examination, is necessary for preoperative diagnosis of pelvic lesions or for the development of a treatment plan.