Radiotherapy takes different time according to the type of disease. Radiotherapy is a local treatment method to treat tumor by ionizing radiation, which is divided into external irradiation and brachytherapy, and is divided into various kinds according to different radiation and technology, such as radiotherapy gamma knife is external irradiation; intracavitary radiotherapy and particle implantation are brachytherapy. For early-stage nasopharyngeal cancer, radiotherapy is used as a radical treatment, which takes 7 weeks; for breast cancer, postoperative adjuvant radiotherapy takes 5 weeks; for cervical cancer, in addition to 5 weeks of external irradiation, 5 times of intracavitary rear-mounted radiotherapy is required; for brain metastasis tumors with more isolated lesions, large split irradiation is required. The cost of radiotherapy varies according to the means of radiotherapy and geographical differences.