Abstract: Bone metastasis from malignant tumor will reduce the survival rate and life quality of patients.As the most two common procedures of evaluating the condition of whole-body skeletal system, both ¹⁸F-FDG PET and ⁹⁹Tc^m-MDP bone imaging can detect early metastasis and stage the cancer, thus helping the treatment.With the help of the theory of these two imaging methods, diagnostic differences and points of focus in different pathological types of bone destruction can be analyzed.Except PET and bone imaging, MRI is also an imaging method with high sensitivity.Moreover, PET-CT, SPECT-CT and some newly-discovered tracers will certainly add new value on detecting bone metastasis by methods of nuclear medecine.