To investigate the relationship between the prognosis and the HER-2 expression and its significance as a prognosis predictor in patients with breast cancer. In 185 samples of breast cancer the expression of HER-2 was immunchistochemically deternined and the survival time of the patients was respectivaly affirmed. 120 patients (64.9%) with complete followed-up data were indudal, of whom 28 patients died (15%). The records of other 65 patients (35.1%) were not available for this study. It was showed that the positive rate for HER2 was 37.3%. There was significant difference between the survival curves in patients exhibiting different grades of HER2 expression (P