Objectives Juvenile idiopathic arthritis (JIA) affects children of all races. Prior studies suggest that phenotypic features of JIA in African American (AA) children differ from those of Non-Hispanic White (NHW) children. We evaluated the phenotypic differences at presentation between AA and NHW children enrolled in the CARRA Registry, and replicated the findings in a JIA cohort from a large center in South Eastern USA. Methods Children with JIA enrolled in the multi-center CARRA Registry and from Emory University comprised the study and replication cohorts. Phenotypic data on Non-Hispanic AA children were compared with NHW children with JIA using Chi-square, Fisher's exact and Wilcoxon rank sum tests. Results In all, 4177 NHW and 292 AA JIA cases from the CARRA Registry, and 212 NHW and 71 AA cases from Emory were analyzed. AA subjects more often had RF-positive polyarthritis in both CARRA (13.4% vs. 4.7%, p=5.3×10-7) and Emory (26.8% vs. 6.1%, p =1.1×10-5) cohorts. AA children had positive tests for RF and CCP more frequently, but oligoarticular or early onset ANA-positive JIA less frequently in both cohorts. AA children were older at onset in both cohorts and this difference persisted after excluding RF-positive polyarthritis in the CARRA Registry (median age 8.5 vs. 5.0 years; p =1.4×10-8). Conclusions Compared to NHW children, AA children with JIA are more likely to have RF/CCP positive polyarthritis, and are older at disease onset, and less likely to have oligoarticular or ANA-positive early onset JIA, suggesting that the JIA phenotype is different in African American children.