Serum immunoglobulin A (IgA) is a biomarker of liver disease severity in adult nonalcoholic fatty liver disease (NAFLD). The objective of this study was to assess whether this is true in pediatric NAFLD. This was a retrospective study of children followed in the Steatohepatitis Center of a tertiary care center (2010–2017). Serum IgA levels, histology and biochemical markers of hepatocellular injury and metabolic dysregulation were collected. Of the 600 children with available serum IgA levels (mean age 14 ± 3 years, 62% boys, 80% non-Hispanic), IgA was elevated in 4%. The group with elevated IgA levels was younger and had a greater representation of Hispanic ethnicity compared with those with normal or low IgA. Body mass index and aminotransferases were not different between the groups. Histology was available for 170 children and was not different in those with elevated, normal and low IgA. In contrast to adults, serum IgA is not a biomarker of liver disease severity in pediatric NAFLD.