Abstract: Childhood and adolescent lymphomas account for 10%-15% of all pediatric cancers. Most cases of pediatric lymphoma involve highly aggressive tumors and extranodal sites. As such, accurate staging and early assessment of therapeutic response are of great value for lymphoma in children and adolescents. Conventional imaging modalities (e.g., ultrasound, CT, MRI, and ⁶⁷Ga) present some limitations in their diagnosis and treatment. ¹⁸F-FDG PET/CT is a new imaging technique that combines the functional data of PET with the morphological information of CT. This article reviews the current role of ¹⁸F-FDG PET/CT in the staging, efficacy evaluation, and follow-up of childhood and adolescent lymphoma and finds that ¹⁸F-FDG PET/CT is more sensitive than other imaging techniques in monitoring lymph nodes and the spleen. By imaging more lesions, the accuracy of ¹⁸F-FDG PET/CT for staging is better than that achieved by traditional imaging methods. At the same time, because of its metabolic changes earlier than the anatomical changes, assessing treatment efficacy promptly and accurately, as well as determining the nature of residual lesions, may be possible. Because of its lower recurrence rate, the trade-offs between monitoring recurrence and radiation exposure during the follow-up period must be weighed.