Background : The Bcl2 gene encodes a protein that blocks apoptosis and might help to promote tumor development if expressed in a hifii percentage. However the mechanisms that regulate bc12 expression in breast carcinoma are unknown, there was a relation between bd:2 expression and low grade tumor and ER positivity in breast cancer. Aim of study To assess the expression of bc12 in breast tumors and its correlation with clinicopathological prognostic factors. Materials and methods All formalin fixed paraffin embedded tissue were retrieved from Department of Pathology of Al-kadhmia Hospital and Teaching Lab. Of Medical City Hospital for the period between Jan. 2003-Jan 2004 Fourty one cases of breast tumors, 7were bengin (fibrocyctic disease 3 cases,fibroadenoma 3cases,fibrocyctic disease with severe atypical epithelial hyperplasia lease) and 34case were malignant (invasive ducts 16 cases, insitu duct carcinoma 9 cases, ivasive lobular carcinoma 6 cases ,insitu lobular carcinoma 3 cases ) . 4 fit hick paraffin sections were prepared For each case,one representetive section was stained with H and E other were stained immunohistochemically for bc12. Twenty cases were stained for ER. Results Five bengin lesions out of 7 (71%) and 17 malignant lesions out of 34 (50%) were bc12 positive. There was significant difference in bc12 expression between invasive ductal and invasive lobular carcinoma (p=0.04) and between invasive ductal and in situ ductal carcinoma (p=0.03.) There was high bc12 expression in low grade tumors but no significant difference in bc!2 expression in different histological grades in both invasive ductal and lobular carcinoma There was a relation between bc12 expression and ER positivity . High bc12 expression was seen in tumors with negative lymph node involvement. No correlation between bc!2 expression and other clinicopathological prognostic factors (age, menopausal stae,tumor size, lymphocytic infiIteration and vascular invasion). Conclusion Bcl2 expression cannt be regarded as independent prognostic factor but it correlates with favorable prognostic factors like low grade tumors, negative lymph node involvement, and ER. positivity.