Abstract: The regulatory role of long non-coding RNA (lncRNA) in cancer radiosensitivity has obtained increasing attention. Radiotherapy is one of the primary treatment methods for cancer, yet some patients experience disease progression or recurrence due to radioresistance. Exploring the regulatory mechanisms of radiosensitivity during cancer radiotherapy and identifying new molecular therapeutic targets are crucial for enhancing the efficacy of cancer radiotherapy. LncRNA can participate in the response of cancer to radiotherapy and regulate cancer radiosensitivity through various pathways, including modulation of the DNA damage response, apoptosis, cancer stem cells, and epithelial-mesenchymal transition (EMT). This study discussed the research progress on the mechanisms of lncRNA in the field of cancer radiotherapy, highlighting their important roles in enhancing tumor radiosensitivity.