There are many imaging manifestations of bone tumors. Generally benign bone tumors, such as osteochondroma, have obvious bone protrusions, and some of them are huge and can reach several centimeters. Some parosteal sarcomas have shadows in the middle, which can be easily confused with ossifying myositis and can be diagnosed by puncture. Most of the metastatic carcinomas are osteolytic, and in some cases, osteogenesis and osteolysis appear simultaneously. Osteolytic changes are easily confused with tuberculosis, which generally destroys cartilage first and narrows the joint space, while bone metastatic cancer generally does not invade cartilage and mainly destroys bone. Bone malignant tumors, such as osteosarcoma, usually do not extend beyond the joint, at the bony end such as the lower femur and upper tibia of the knee, where osteosarcoma and giant cell tumor of bone are more common. In addition, bone tumor imaging changes must refer to the age, such as osteosarcoma usually occurs in the age of 15-25 years, and now the age of onset becomes younger, in the clinic there has been a 9-year-old child with osteosarcoma.