半束照射是伴随着新一代加速器的问世而应用于临床的一种新的放疗技术，它能减少正常组织的受照剂量，防止照射野相交处出现剂量热点和冷点。自１９９１年以来，作者将这一技术用于乳腺癌、直肠癌、肺癌、头颈部肿瘤等多种肿瘤的放射治疗，并形成了一整套的技术规范。 Semi-beam irradiation is a new radiotherapy technique that is applied clinically with the advent of a new generation of accelerators. It reduces the dose of normal tissue and prevents the occurrence of dose hot spots and cold spots at the irradiation field. Since 1991, the authors have used this technique for radiation therapy in a variety of tumors, including breast cancer, rectal cancer, lung cancer, head and neck cancer, and formed a complete set of technical specifications.