In recent years, heavy ion beams have received great attention in the field of malignant tumor radiotherapy due to their radiation physics and biological characteristics. The high rate of local tumor control is one of its advantages, but the control rate of metastatic lesions is still crucial in the treatment of most malignant tumors. Clinical studies on the combined conventional radiotherapy and immunotherapy suggest that the combination of the two can not only control the primary lesions, but may also reduce or completely eliminate distant metastatic lesions. High linear energy transfer radiation, especially heavy ion beams, may have stronger potential in combined immunotherapy. Therefore, this article focuses on the basic research progress of heavy ion beams regulating anti-tumor immune effects and their combined application with immunotherapy.