Magnetic resonance is a very important method to check cancer metastasis, especially for intracranial metastasis, spinal bone metastasis, and cartilage and soft tissue metastasis of the extremities. For liver metastases, the value of MRI is also very high, so MRI is a very useful tool for detecting distant metastases of cancer. MRI also has some limitations, for example, tumors of the lung are not suitable for MRI examination. Other than that, distant metastases of other tumors can basically be detected by MRI, especially for metastases in the liver, head, soft tissues of the limbs and vertebrae, which is a very sensitive method.