Anemia in rheumatoid arthritis (RA) is multifactorial. Iron deficiency, either definite or relative (defect in iron utilization), exists in RA patients with anemia. Intravenous iron therapy is indicated in severe and symptomatic cases or those with conditions precluding use of oral iron, but its safety and long-term efficacy have not been well-established. Forty severe anemic (hemoglobin < 9 g/dL) RA patients with or without demonstrable bone marrow iron stain were enrolled in this study. Fractionated administration of intravenous iron saccharate was undertaken and the median follow-up time was 1 year. All patients exhibited significant elevations of hemoglobin 3 months after treatment, which were more pronounced in the nonstainable iron marrow subjects {median (interquartile range): 3.8 (2.9-4.8) g/dL versus 2.9 (2.0-3.0) g/dL, p < 0.01}. Thereafter, hemoglobin remained at a plateau level that lasted during the observation period. Throughout the whole course, none of the cases exhibited side effects or flare up of disease activities. The use of intravenous iron saccharate, preferably administrated in a fractionated way, is effective in the correction of severe anemia in RA patients, especially those with nonstainable iron marrow.