Triple-negative breast cancer (TNBC) typically manifests as higher invasive carcinoma correlated with a worse prognosis that primarily relies on chemotherapy. There is growing evidence that nitric oxide (NO) donor drugs have the potential for anticancer therapy. On this basis, we constructed and evaluated a novel coumarin-furoxan hybrid as an effective antitumor candidate drug. exhibits low IC values in three TNBC cell lines and inhibits colony formation and DNA synthesis, probably due to the release of high concentrations of NO in mitochondria, which induces oxidative stress, mitochondrial dysfunction, and apoptosis. Further research suggests that might destroy mitochondria by opening the mitochondrial permeability transition pore (mPTP), depolarizing the mitochondrial membrane potential (MMP), and promoting the release of cytochrome into the cytoplasm. Intrinsic apoptosis is induced finally, along with Akt/Erk signaling suppression. Additionally, underregulates the Epithelial-mesenchymal transition process to inhibit cell migration and invasion. In 4T1 subcutaneous and hematogenous models of mice, therapy suppresses the tumor growth and prevented lung metastasis with favorable biosafety. Our results provide insights into in TNBC treatment and validate the contribution of NO donors in tumor therapy.