The study was conducted on 85 samples of blood and tissue collected from 85 patients, histopathologically proven breast cancer, in addition to 15 patients with benign breast lump as control group. The study were included three parts: the first part in the oxidative stress the detoxification mechanism mediated by glutathione and its related enzymes were evaluated indirectly by measuring the changes in the plasma and tissue malondialdehyde-like-material. glutathione. glutathione reductase and tissue glutathione-s-transferase in 85 patients and 15pateints as control group. In the second part the role of p53 and bcl-2 in breast cancer, were correlated to the grade and stage of tumor included 30 samples of patient and 5 as control group. The expression of the previously mentioned genes was studied by immunohistochemistry (IHC). The third part was chromosomal analysis study which was conducted on all cases of the patients. The results indicated that the plasma malondialdehyde-like-material and glutathione in patients were decreased significantly as compared with control group (P<0,05). In addition plasma glutathione reduclase increased significantly when compared with control group (P<0.01). This result may indicate increase of oxidative stress in breast cancer patient. In the tissue, a significant increase in glutathione concentration but decrease glutathione reductase, glutalhionc-s-transferase and malondialdehyde-like-material were compared with control group (P<0.05). Suggesting an increase in the delivery of many toxic agents including reactive oxygen species (ROS) and other compounds contain free radical capable ofredox cycling into cancer cell. The results of p53 and bcl-2 were correlated with grade and stage of tumor were found role of p53 and bcl-2 in breast cancer through increase protein expression (52% & 64%) respectively in breast cancel-tissue especially bcl-2. The result of cytogenetic study of 85 samples of breast cancer by direct preparation method and short-term culture, numerical abnormalities were detect in 11 cases in the study. The result was of numerical abnormalities chromosomes in most groups. The role of expression p53 and bcl-2, and the increase in the delivery of many toxic agents' as well as abnormal chromosomes can be recorded as some prognostic factors in breast tumors.