Abstract: Triple-negative breast cancer (TNBC) is a subtype of breast cancer defined by the lack of expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 (Her-2).TNBC is characterized by its onset among females at a very young age, high invasiveness and histological grades, and easy metastasis to the internal organs.This type of breast cancer is prone to visceral metastases and rapid progression, thereby resulting in short survival and unfavorable prognosis.Therapeutic tools against TNBC are limited because endocrine-and Her-2-targeted therapies are both ineffective.Synthetic lethal strategy means that two genetic mutations cause cell death.However, cells survive if only one mutation gene exists in the case.In these two mutation genes, if one is the oncogene, the other can become the potential "target gene." This targeted inhibitor can then selectively kill malignant tumor cells through gene mutation, i.e., it can selectively kill the tumor without harming normal cells.This strategy of lethal synthesis for studies on new drugs against TNBC provides innovative ideas.Meanwhile, the breast cancer susceptibility gene BRCA-1 can synergistically repair DNA damage with poly (ADP-ribose) polymerase 1 (PARP-1).PARP-1 is reportedly one of the new targets, and PARP-1 inhibitors can become a new drug for anti-TNBC targeted therapy.