Breast cancer is the most common type of cancer which leads to many deaths among women. Olive because of its antioxidant compounds is considered as a candidate in controlling and prevention of cancer. In this study the impact of Nano Oleuropein of olive in densities, namely 0 ppm, 300 ppm and 600 ppm treatment on the protein profile in MCF-7 cell line using two-dimensional electrophoresis and MALDITOF-TOF was examined. Results of changes in expressed protein spots showed that among 317 spots, four proteins include CLIC1, HSPB1, PSMD7, and SULT1A2 had significant differential change which were confirmed with level less than 1% in Masscot. These proteins are important factors in the anti-proliferative pathway and induction of apoptosis pathway. Therefore, by inducing the incensement of expression of (PSMD7 and CLIC1) proteins by Oleuropein treatment, cancer cells of MCF-7 with the help of anti-proliferation and apoptosis mechanisms play a major role in their containment and a significant reduction in expression (SULT1A2 and HSPB1) as a way to support the induction of apoptosis pathway is presented by the Oleuropein. Oleuropein ensures further investigations to prove its utility in preventing/treating breast cancer.