Background: Breast cancer is the most common gynecological malignancy and one of the leading causes of death in women worldwide. Since antiquity to date, the saga of usage of plants as medicines has been the mainstay among the people. In Ayurvedic and Unani systems of medicine, Rheum emodi (RE) commonly known as Revand chini or Rhubarb is an important medicinal plant. It is a perennial herb belonging to family Polygonaceae and has antimicrobial, anticarcinogenic, and anti-inflammatory properties. The rhizomes of RE have anthraquinone derivatives such as emodin, aloe-emodin, rhein, emodin glycoside, and chrysophanol glycosides. Objective: In this study, we have investigated the anti-cancerous potentials of RE ethanolic extract on human breast adenocarcinoma cells MCF-7 and its antimicrobial effect against selected pathogenic bacterial strains. Materials and Methods: The apoptotic and anti-proliferative potentials of RE on human breast adenocarcinoma cells MCF-7 were observed through cell viability (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT]), reactive oxygen species (ROS) generation, nuclear fragmentation, and mitochondrial membrane potential (MMP) analysis. Antimicrobial activity of RE was screened through well-diffusion assay. Results: The results show that RE significantly inhibits the proliferation and induces apoptosis in MCF-7 cells of breast adenocarcinoma in a dose-dependent manner. The MTT cellular viability assay and morphological study reveal that RE significantly induces morphological alterations in MCF-7 cells in a dose-dependent manner and thus inhibits cell proliferation. The cytotoxic effect of RE through the induction of apoptosis is evident by the disruption of MMP, nuclear fragmentation, and ROS accumulation. In addition, we have found that RE is potent enough to decrease the microbial activity of selective bacterial strains. Conclusion: The findings demonstrated that RE promotes significant apoptosis in breast adenocarcinoma MCF-7 cells. Therefore, RE may be a potent candidate that aids for adjuvant cancer treatment though further studies are needed to elucidate the comprehensive mechanistic pathways