This project uses HER2 protein as the target group of radiodrugs to explore the diagnostic efficacy, safety and metabolic characteristics of 68Ga-Her2-affibody in the expression status of HER2, aiming to provide a new imaging method for the determination of HER2 status in breast cancer At the same time, it also provides new methods and means for early diagnosis, accurate staging, recurrence judgment, treatment decision-making and prognosis judgment of malignant tumors such as lung cancer, gastrointestinal cancer and bladder cancer, and provides scientific basis for precise treatment of malignant tumors.