6615 Background: Adolescent and young adult (AYA) patients (15-39 years) are an underrecognized population with high risk of select malignancies. Compared to pediatric and adult patients, AYA patients have not achieved improvements in cancer survival. No studies have evaluated overall survival (OS) and stage at diagnosis among all 5 federally recognized races in the US. Here we aim to investigate OS and stage at diagnosis among AYA patients by race. Methods: A retrospective cohort study of AYA patients diagnosed between 2004-2017 was conducted with the National Cancer Database. Patients with the 10 deadliest AYA cancers with at least 6 months of follow-up were included. Primary endpoints were OS (time from diagnosis to death) and late stage at diagnosis (stage III/IV or Grade III/IV for central nervous system [CNS] cancer). Kaplan-Meier estimates and log-rank tests assessed OS. OS and late stage were evaluated by race using multivariable Cox proportional hazard (adjusted hazard ratio [aHR]) and logistic (adjusted odds ratio [aOR]) regressions, respectively, with 95% confidence intervals (95%CI). All regressions were adjusted for sociodemographic and cancer characteristics. Results: 291,899 AYA patients were included: 64% female, 65% stage I/II, and 62 month median follow-up. Cancer sites included 27% breast, 16% lymphoma, 13% melanoma, 11% testis, 9% CNS, 7% colorectal, 7% cervix, 5% sarcoma, 3% ovary, and 2% lung. Race included 82.3% Non-Hispanic White (NHW), 14.0% Black, 2.9% Asian, 0.5% American Indian and Alaska Native (AIAN), and 0.3% Native Hawaiian and other Pacific Islander (NHPI). OS differed for all cancers by race (p<.0001), except for lung (p=.008), CNS (p=.32), and ovary (p=.28). OS was significantly inferior for NHPI, Black, and AIAN but superior for Asian, versus NHW (Table). NHPI had inferior OS (aHR, 95%CI) for melanoma (4.5, 2.0-10.0), colorectal (1.8, 1.3-2.4), lymphoma (1.7, 1.1-2.1), and cervix (1.6, .1-2.4) cancers. Black patients had inferior OS for melanoma (1.6, 1.2-2.2), lymphoma (1.5, 1.4-1.6), and breast (1.4, 1.3-1.4) cancers. Asian patients had superior OS for breast (0.7, 0.7-0.8) and lung (0.7, 0.6-0.9) but inferior survival for testis (1.9, 1.3-2.9) cancers. AIAN patients had inferior OS for colorectal (1.4, 1.0-1.9). Late stage at diagnosis was higher for NHPI, Black, and Asian patients, compared to NHW patients (Table). Conclusions: Both NHPI and Black AYA patients with cancer have higher risk of death and late stage disease at diagnosis, compared to NHW patients. Our data reveal racial disparities among Indigenous AYA patients masked by prior data omission. [Table: see text]