The role of iron supplementation in treating the anaemia of systemic-onset juvenile chronic arthritis is not clear. Eight affected children with severe persistent anaemia unresponsive to oral iron therapy were treated with intravenous iron saccharate. From a median post-oral-iron value of 8.0 g/dL (range 6.5-9.5), haemoglobin rose to 11.0 g/dL (10.1-12.1) (p = 0.01). The concentration of serum transferrin receptor, an indicator of iron deficiency, before intravenous therapy correlated with the increase in haemoglobin (r = 0.88, p < 0.01). Intravenous iron saccharate could be an effective treatment for chronic anaemia in this condition, especially with iron deficiency not responsive to oral iron.