Background: This study used a linked dataset consisting of all childhood cancers recorded over the course of 10 years in New South Wales (NSW), Australia, to evaluate the hospital and emergency department costs (from a payer perspective) and resources used by patients with childhood cancer. We also analyzed determinants responsible for high-frequency hospital admissions, hospital length of stay (LoS), and hospital costs. Methods: We analyzed linked data at the individual patient level for a retrospective cohort of 2,966 patients with cancer aged <18 years with a diagnosis date between 2001 and 2012 from the NSW Central Cancer Registry, Australia. We reported costs and use of hospitalization and emergency department presentation 1 year before the date of diagnosis, 1 year after diagnosis, and 2 to 5 years after diagnosis. We also examined the association between cancer types and hospital admission and hospital costs from the payer perspective. Patient characteristics associated with the frequency of hospital admissions, hospital LoS, and hospital costs were also determined using a generalized linear model. Results: Most hospital admission costs occurred in the first year after diagnosis, accounting for >70% of hospital costs within 5 years after diagnosis. The estimated median annual cost of hospitalization in the first year after diagnosis was A$88,964 (interquartile range [IQR], A$34,399–A$163,968) for patients diagnosed at age 0 to 14 years and A$23,384 (IQR, A$5,585–A$91,565) for those diagnosed at age 15 to 17 years. Higher frequency of hospital admissions, hospital LoS, and hospital costs were significantly associated with younger age at cancer diagnosis, cancer metastases, and living in remote/disadvantaged socioeconomic areas. Conclusions: Our study represents one of the first in Australia to include detailed hospitalization cost information for all childhood cancer cases. This study highlights the high hospital use by pediatric patients and the importance of early diagnosis. Our findings also demonstrate the health inequities experienced by patients from remote areas and the lowest socioeconomic areas.