Objective: To study the relationship between the expression of PS2 protein and Estrogen (ER) and Progesterone Receptor (PR) status and their prognotic value in breast cancer. Methods: Using the immunohistochemical method, PS2 protein expressions were detected in 105 cases with breast cancer. Results:The positive rate of PS2 protein was 50.48% (53/105) in 105 cases. The positive rate of PS2 in the patients who survived five years or more was 56.96% (45/79), which was higher than that of those who lived less than five years (30.77%, 8/26). In the ER, PR (+) patients, the positive rate of PS2 was higher (76.74%, 33/34), than that of those with ER, PR (-) (22.5%, 9/40). Conclusions:Our results suggest that the expression of PS2 protein was positively correlated with the S-year-survival and that of ER and PR in breast cancer. It is considered that PS2 may be as a prognostic predictor, and detection of PS2 protein expression was useful for a guiding treatment of breast cancer.