A case study is presented of a two-year-old girl with hepatoblastoma treated with proton beam therapy (PBT). The patient underwent magnetic resonance imaging (MRI), computed tomography (CT), and ultrasonography and began treatment with cisplatin and doxorubicin chemotherapy until the tumor developed resistance to the drugs. PBT and adjuvant intravenous chemotherapy was used as an alternative to liver resection or transplantation. The patient was cancer-free at a follow-up 16 years later.