Even though the use of erythropoietin and intravenous iron has improved the treatment of anemia in hemodialysis patients, a considerable proportion of these patients still have anemia. The aim of this study was to identify predictors of anemia in a hemodialysis population. In a single-center hemodialysis unit, all patients were studied with blood tests and their medication recorded during a period of 22 months. Correlations with hemoglobin (Hb) were performed with a simple regression or a t test. Variables that reached 5% significance were entered in a multiple regression analysis. Selected variables were presented in quartiles with levels of Hb. Mean Hb was 11.3 g/dL, and 53 patients (40%) had Hb<11.0 g/dL. In the simple regression analysis Hb correlated positively with s-iron, CHr, s-albumin, and doses of sevelamer, and negatively with sedimentation rate (SR), ferritin, base excess, and doses of erythropoietin. In the multiple regression analysis erythrocytes SR was the only variable that remained significant. Elevated SR is the strongest predictor of anemia in hemodialysis patients receiving adequate treatment with erythropoietin and intravenous iron. Patients using high doses of sevelamer had higher Hb levels than patients using low doses.