Radiation therapy induces the death of tumor cells directly or indirectly through radiation. The radiation used for treatment includes photon and particle beams, which can destroy the double helix structure of tumor cell DNA, so that the cells cannot replicate and proliferate, thus achieving the therapeutic effects. Since the discovery of radiation 100 years ago, concretely, Roentgen reported the discovery of X-ray in 1895 and Marie Curie reported the discovery of radium in 1896, their biological effects were soon recognized and gradually applied to the treatment of some superficial tumors. The radiation therapy techniques for hepatocellular carcinoma have made great progress from initial whole liver radiation therapy and moving strip whole liver radiation therapy to three-dimensional conformal radiation therapy (3D-CRT) and intensity-modulated radiation therapy (IMRT), to current IGRT including stereotactic body radiation therapy (SBRT).