Introduction: Breast cancer is the most common cancer in women, ahead of colorectal cancer and lung cancer. Among the protein substances or hormones produced by cancerous tissues are tumor markers such as CA15-3 and CEA, which are specific to breast cancer. Materials and Methods: Our work consisted of conducting a retrospective clinical study at the Oncology Center of Relizane, covering the period from January 1, 2019, to December 31, 2022. This research focused on 470 cases of breast cancer, including 457 women and 13 men, with ages ranging from 22 to 90 years. The objective of this study was to evaluate the significance of tumor markers in the management of breast cancer. Results and Discussion: Our investigation demonstrated that the predominant histological type was stage I and II carcinoma, with co-dominance between the involvement of the left and right breasts. The HER2+ molecular type was the most dominant in our study. Tumor marker results showed that the levels of CA15-3 and CEA were elevated in patients who had developed metastasis, with 89.19% and 32.96% of cases respectively. A statistically highly significant relationship was found between the development of metastasis and the levels of tumor markers CA15 3 and CEA (p=0.0001). Conclusion: Tumor markers are a crucial tool for diagnosing the patient's condition, anticipating and monitoring an individual's response to certain treatments, and detecting cancer recurrence.