Over the last few years, increased evidence has supported the role of iron dysregulation in the pathogenesis of multiple sclerosis (MS), as iron is essential for myelin formation and oxidative phosphorylation. We studied indices of iron metabolism, such as serum iron, ferritin, transferrin and soluble transferrin receptor (sTFR) levels in 27 MS patients. Seven patients had chronic progressive active disease (CP-A), six had chronic progressive stable (CP-S), ten had relapsing remitting active (RR-A) and four had relapsing-remitting stable (RR-S) disease. sTFR levels were found to be significantly higher in CP-A (P = 0.021) and RR-A (P < 0.004) patients than in controls. sTFR levels were also elevated in CP-S patients but did not reach significance (P = 0.064). sTFR values in RR-S patients were comparable to those found in controls (P = 0.31). Ferritin levels were significantly elevated only in CP-A patients (P < 0.002). Patients of the CP group had significantly higher ferritin values than the RR patients (P < 0.004). Haemoglobin values as well as iron and transferrin levels were within normal limits in all patients. In conclusion, the increased serum sTFR and ferritin levels in nonanaemic MS patients with active disease reflect the increased iron turnover. The mild elevation of sTFR levels in CP-S patients may indicate active inflammation with ongoing oxidative damage that is not detectable by history or examination.