Technical advancements in imaging, in radiation therapy (RT) planning and RT delivery, have facilitated the safe delivery of conformal radiation therapy to patients with unresectable hepatocellular carcinoma (HCC). Although experience in liver cancer RT is limited, the RT technologies and tools to deliver RT safely are being disseminated rapidly. A variety of doses and RT fractionations have been used to treat HCC, and RT has been used in combination with other therapies including transarterial hepatic chemoembolization (TACE). Outcomes following RT alone or RT and TACE appear better than outcomes following similar historical controls of TACE alone, however, randomized trials of RT are needed. The first site of recurrence following RT is most often within the liver, away from the high dose volume, providing rationale for combining RT with regional or systemic therapies. Given the vascular properties of HCC, the combination of RT with anti-VEGF targeted agents may improve outcomes further.