Abstract: Triple-negative breast cancer is a special type of breast cancer, which has become a difficult problem in clinical practice because of its high invasiveness, easy recurrence and easy metastasis. p90 ribosomal S6 kinase (RSK) is a signaling molecule downstream of Ras-Raf-MEK-ERK signaling pathway. Its family member RSK2, which is highly expressed in triple-negative breast cancer, is closely associated with tumor cell proliferation, apoptosis and invasion, making it a promising target for the treatment of triple-negative breast cancer. This article has reviewed the role of RSK2 in the development of cancer and the research progress of its inhibitors, so as to provide ideas and references for the development of targeted drugs for triple-negative breast cancer.