Abstract: Objective To detect the expression of NOTCH1 and NF-κB in breast cancer cells MDA-MB-231 treated by curcumin. Methods Breast cancer cell lines MDA-MB-231 were cultured in vitro and treated by curcumin with different dosages of 1.25, 5.0, 20.0μmol/L and different times 24, 48，72h. The changes of the mRNA and protein expression of NOTCH1 and NF-κB were analyzed by RT-PCR and western blot, and MTT assay was used to measure cell proliferation. Results The proliferation rate of human breast cancer cells treated by curcumin for 72 hours was significantly inhibited and the inhibition rate is (52.0±0.42)% (P<0.05). The mRNA level of NOTCH1 and NF-κB was decreased significantly after treated by curcumin on dose-and time-dependent manner(P<0.05). Moreover, the changes of protein correspond with the mRNA level. Conclusion Cucumin can down-regulate the expression of NOTCH1 and NF-κB，and these changes suggested a dose- and time-dependent manner. Curcumin may be a novel strategy for the treatment of patients with breast cancer.