Background: Comprehensive genomic profiling (CGP) was widely adopted in Japan after its coverage by national healthcare insurance began in June 2019. We investigated the clinical utility of CGP in pediatric and adolescent young adults (AYA) solid tumor patients. Procedure: Between November 2017 and December 2019, 13 patients who progressed with or who were likely to progress with standard therapies were recruited to the PROFILE-F study to undergo CGP using either FoundationOne® CDx or FoundationOne® Heme. Results: The median age was 28 years old. Tumor types were as follows: neuroblastoma (n=1), Wilms’ tumor (n=1), rhabdomyosarcoma (n=2), Ewing sarcoma (n=1), gastric cancer (n=1), rectal cancer (n=1), osteosarcoma (n=1), neuroendocrine tumor (n=2), salivary gland carcinoma (n=1), tracheal adenoid cystic carcinoma (n=1), and thymic cancer (n=1). In 92% of cases, at least one genomic alteration was identified, including CDKN2A (four cases), TP53 (three cases), and MYC (two cases). Actionable aberrations were found in 10 cases (77%), and a clinical trial candidate was found in seven cases (54%). However, no patients were able to receive biomarker-matched therapy according to their genomic alterations. Conclusions: Further efforts to increase basket trials and collection of clinical genomic data to predict response are necessary to advance precision cancer medicine in pediatric and AYA populations.