Cancer is one of the causes of death in the world. One of the steps of cancer treatment is through chemotherapy (5FU). However, the effectiveness of 5FU is still bad, so, it needs such as agent of chemotherapy combination to increase the cancer cells sensitivity, so the effectiveness of 5FU increases. The bisoprolol tablets have been reported to improve the life quality of cancer patients. In addition, the β1-blocker group has also been investigated to inhibit proliferation in two cell lines lung cancer. The purpose of this study was to determine the anticancer activity of bisoprolol and 5FU combination against T47D breast cancer cells. The cytotoxic test method which used was MTT Assay with 0 hours, 24 hours, 48 hours, and 72 hours of incubation time at 370C and at level 5% of CO2. Cytotoxic test results showed that bisoprolol has moderate cytotoxic activity with 104.62 μg/mL of IC50. The combination of bisoprolol and 5FU with various concentrations showed a strong synergistic effect (CI <0.3) with consentration bisoprolol 50 μM + 5FU 200 μM and bisoprolol 50 μM + 5FU 500 μM. T47D cell proliferation rather can be inhibited and decreased in cells which is treated with combination of bisoprolol and 5FU than the controlled cells. The combination of bisoprolol and 5FU can increase the sensitivity of 5FU, so, it can inhibit the proliferation of T47D cells greater than the treatment of a single bisoprolol and 5FU tablet.