Background: To evaluate whether ABO-Rh blood groups have significance in the treatment response and prognosis in patients with non-metastatic breast cancer. Materials and Methods: We retrospectively evaluated files of 335 patients with breast cancer who were treated between 2005 and 2010. Demographic data, clinic-pathological findings, treatments employed, treatment response, and overall and disease-free survivals were reviewed. Relationships between clinic-pathological findings and blood groups were evaluated. Results: 329 women and 6 men were included to the study. Mean age at diagnosis was 55.2 years (range: 26-86). Of the cases, 95% received chemotherapy while 70% were given radiotherapy and 60.9% adjuvant hormone therapy after surgery. Some 63.0% were A blood group, 17.6% O, 14.3% B and 5.1% AB. In addition, 82.0% of the cases were Rh-positive. Mean follow-up was 24.5 months. Median overall and progression-free survival times were 83.9 and 79.5 months, respectively. Overall and disease-free survival times were found to be higher in patients with A and O blood groups (p<0.05). However rates did not differ with the Rh-positive group (p=0.226). In univariate and multivariate analyses, ABO blood groups were identified as factors that had significant effects on overall and disease-survival times (p=0.011 and p=0.002). Conclusions: It was seen that overall and disease-free survival times were higher in breast cancer patients with A and O blood groups when compared to those with other blood groups. It was seen that A and O blood groups had good prognostic value in patients with breast cancer.