Tumors can be found in bones, and there are benign and malignant bone tumors. Malignant bone tumor, which is often referred to as “bone cancer”, has two categories: primary and secondary. After tumor occurs in other tissues and organs outside the bone, it can also be metastasized to the bone in late stage, which is called “bone metastasis cancer” or “bone metastasis tumor”, so it is not “bone cancer” in real sense. Primary “bone cancer”, most commonly called “osteosarcoma”, usually occurs between 10-25 years old, and there are many types of malignant “bone cancer”; the most common “bone cancer” in middle-aged and old people is “multiple bone cancer”. “The most common type of bone cancer that occurs in middle-aged and elderly people is “multiple myeloma”. Since the causes of tumor occurrence are not completely clear, some of them are related to heredity, while bone malignant tumors, which are often disseminated, do not seem to be clearly related to heredity. However, according to many cases, it can be seen that adolescents have particularly vigorous bone growth and metabolism, which can easily produce mutations and lead to the emergence of osteosarcoma. Multiple myeloma, which is born in middle and old age, is a tumor of the hematopoietic system, and its manifestations are also multiple and systemic. Benign bone tumors are often asymptomatic in the early stage, but if they grow outside the bone, they may cause pain or functional problems due to compression of the surrounding soft tissues, and benign tumors may also cause structural changes in the bone and weaken the force-bearing effect, resulting in pathological fractures. However, such pathological fracture is more common in “metastatic bone cancer” and osteoporotic slow aging, and the differentiation between them is very important clinically; bone malignant tumor, due to fast growth, often has obvious swelling and pressure pain of limbs, and even skin fever and anger of blood vessels. The direct reaction of bone cancer is pain, which is a different kind of pain from general pain, and the most significant feature is quiet pain, and the more quiet it is, the more painful it is. Generally, primary “bone cancer” occurs in the long bones of limbs, which is common among teenagers; secondary “bone cancer” is mostly found in the pelvis, spine and femur, and is mostly seen in middle-aged and old people, which is often caused by the malignant change of the original benign bone lesion.