Chest wall metastasis of breast cancer can be diagnosed through chest CT, PET-CT, histopathological biopsy and other examinations. 1. Chest CT examination: Chest CT scanning and enhancement can check whether there are soft tissue lumps, destruction of bones in chest wall, thickening of pleura, etc., and the results can determine whether there are chest wall metastases. 2. PET-CT examination: PET-CT examination can show the situation of many parts of the body, and can indicate the location and scope of metastasis, etc. Through the examination results, we can judge whether there is chest wall metastasis or not. 3. Histopathological biopsy: further histopathological biopsy of soft tissue mass found by CT examination and PET-CT examination can determine whether it is chest wall metastasis of breast cancer. It is suggested that patients should go to the hospital in time to improve the examination under the doctor’s guidance, so as to clearly diagnose whether it is breast cancer metastasis in chest wall.