We estimated glycated ("glycosylated") hemoglobin in erythrocytes of hemodialyzed uremic patients by the aminophenylboronic acid affinity-chromatographic method and by an ion-exchange chromatographic method. As expected, apparent HbA1 concentrations were above normal in the uremic patients, owing to interference by the carbamylated hemoglobin. However, there was no significant difference between values for uremic and normal subjects when glycated hemoglobin was measured by the affinity method. Evidently it is unaffected by the presence of hemoglobin species modified by reactants not displaying a cis-1,2-diol group, such as carbamylated hemoglobin. For this reason it is preferable to the ion-exchange chromatographic method for accurate measurement of glycated hemoglobin.