Introduction & Objective: Breast cancer is the major cause of death in 40-44 years old females and is the most common site specific cancer in them. The incidence of breast cancer is 1 of 8 female person. Some of prognostic factors are tumor size, pathologic grade, auxillary lymph nodes, ER, PR, P53 and HER-2-neu that are effective in prognosis and therapeutic plan. Frequency and relationship of the last four markers with each other and with menopause and age are discussed in this article. Materials & Methods: Two hundred female patients with pathology documented ductal or lobular breast cancer were studied in a 3 years period by IHC method for ER, PR, P53 and HER-2-neu. Results: All the patients were female with the mean age of 49.6 years (SD=+11.36) and the range of 26 to 81 years old. ER was positive in 142 cases (71%), PR was positive in 131 cases (65.5%), P53 was positive in 63 cases (31.5%), and HER-2-neu was positive in 143 cases (71.5%). There was a significant positive correlation between ER and PR (P<0.05). There was a significant negative correlation between P53 and ER or PR. There was a significant positive correlation only between ER and age. There were not any correlations between each marker and menopause. Conclusion: HER-2-neu indicates the worst prognosis and better response to chemotherapy. There was a significant difference of HER-2-neu in the reference texts (25%-37%) and this research (71.5%), which may be caused by genetic differences.