Equal access to clinical trial enrollment is important to ensure that findings are generalizable to the broader population. This study aimed to evaluate disparities in enrollment on pediatric oncology clinical trials. We assessed the relationship between patient characteristics and enrollment on COG trial AAML1031 in a cohort of pediatric patients with AML in the Pediatric Health Information System. The associations of enrollment with outcomes were evaluated. Non-Hispanic Black patients, infants, and patients from zip codes with a lower proportion of poverty were less likely to enroll (30% vs. 61%, p = .004; 34% vs. 58%, p = .003; 46% vs. 58%, p = .02). On-therapy mortality was similar among enrolled and nonenrolled patients (7.3% vs. 8.9%, p = .47). Differences in early mortality were more pronounced among nonenrolled patients compared to enrolled patients (3.0% vs. 0.5%, p = .03). Understanding the etiology of these disparities will inform strategies to ensure balanced access to clinical trials across patient populations.