With the continuous progress of radiation therapy technology, the position of radiation therapy in tumor treatment has become increasingly important. In the treatment of many early stage chest tumors, especially early stage non-small cell lung cancer patients, the use of stereotactic radiotherapy can basically achieve the same effect as that of surgical treatment. Radiotherapy is one of the three major means of treating malignant tumors. Like surgery, it is a local treatment for tumors, which mainly refers to the use of various kinds of rays with different energies to irradiate the tumor tissues, so as to achieve a therapeutic method of inhibiting and killing cancer cells. Sixty to seventy percent of tumor patients need to receive radiotherapy in the course of treatment, and the contribution of radiotherapy to the cure of tumor reaches more than 40%. In the past, conventional radiotherapy was given to patients once a day, with a standard, relatively small dose, for 25 to 30 consecutive treatments. Stereotactic radiotherapy, which is the use of a single high-dose irradiation, treatment can generally be completed in three times, in three days to a week’s time can be completed. In addition, traditional radiotherapy irradiation volume are relatively large, and the surrounding tissue will be damaged. Stereotactic radiotherapy, on the other hand, is much more accurate and concentrates the dose on the tumor site, while the surrounding normal tissues receive a lower dose, which greatly reduces side effects and comorbidities. With the advancement of diagnostic level, the early detection rate of tumors is getting higher and higher, and clinicians have gained more chances to preserve patients’ organ functions and improve their quality of life. Today’s radiotherapy integrates a series of new technologies such as stereotactic positioning, modern imaging technology, computer technology, etc. Some malignant tumors, such as nasopharyngeal cancer, laryngeal cancer, cervical cancer, etc., can be radically cured by radiotherapy alone without surgery. For some tumors that require surgical resection, such as lung cancer, colorectal cancer, esophageal cancer, etc., radiotherapy before surgery can shrink the tumors, reduce the risk of surgery, and improve the efficacy of healing and the quality of survival of patients. Some tumors that were not suitable for radiotherapy or patients who cannot be operated in the past can also receive good results from modern radiotherapy technology. Above is the relevant introduction that radiotherapy can cure early lung cancer. Radiotherapy has become a major means of treating malignant tumors, and early treatment is more effective, for this reason, people need to have regular checkups to find out the disease in time and treat it as soon as possible.