Abstract: Objective: To investigate the diagnostic value and the relationship with clinicopatho-logical features of total and free prostate-specific antigen(PSA) in twomen with breast cancer. Methods: Using the microparticle enzyme immunoassay system, the concentrations of these markers in the sera of 85 women with breast cancer and in 30 healthy women were measured. Rseults: Free PSA level was significantly higher in women with breast cancer than that in healthy women(P<0.05). The percentage of free PSA predominant subjects was 37.6% in breast cancer patients and 3.3% in healthy women. In women with breast cancer, total PSA positivity was 23.5% and free PSA positivity was 27.1%. When compared to negatives, total PSA positive patients had a higher percentage of lymph node involvement tumours (P>0.05). However, patients with predomonant free PSA had a higher percentage of early stage than patients with predominant PSA -ACT. Conclusion: This study indicates clinical significance of preoperative measurement of serum total and free PSA in diagnosis and prognosis of women with breast cancer.