Triple-negative breast cancer (TNBC) is the most aggressive sub-type of breast cancer, mainly affecting premenopausal women. As it neither expresses hormone receptors nor overexpresses HER2 receptors, it is difficult to tackle this deadly disease effectively. It is a well-known fact that phytochemicals have remarkable therapeutic potential in the prevention and treatment of different disorders. One of the well-known phytochemicals, ellagic acid (EA) has shown better efficacy in the prevention and treatment of cancer in many preclinical and clinical settings. Therefore, in this study, ellagic acid gold nanoparticles (EA-AuNp) were synthesized and characterized to passively target TNBC cells through EPR effect. EA-AuNp were prepared using the direct reduction method and characterized by UV–Visible spectroscopy, DLS, XRD, EDX, TEM and FT-IR spectra. We found that it significantly suppressed the TNBC cell proliferation (IC50 12 μg/ml) compared to EA alone (IC50 36 μg/ml). Flow cytometry and live and dead assays revealed that EA-AuNp induced more cell death in TNBC cells compared to EA alone. Further, western blot analysis substantiated that EA-AuNp induced apoptosis by regulating the expression of Bcl-2, survivin, caspase 3 and caspase 9. In conclusion, EA-AuNp has high anti-cancer potential and additional preclinical and clinical studies are highly recommended.