[en] Objective: To study the significance of changes of serum levels of ferritin (SF), folic acid (FA) and vitamin B₁₂(VB₁₂) in hypothyroidism patients complicated with anaemia. Methods: Serum SF, FA and VB₁₂ contents were determined with CLIA in 73 hypothyroidism patients and 40 controls. Whole blood analyses were performed with impedance method. Results: In the diseased group, SF, FA and VB₁₂ levels were significantly lower than those in the controls (p < 0.01). Conclusion: Determination of SF, FA, VB₁₂ levels combined with whole blood analysis in those patients might be helpful in defining the type of anaemia and could possibly save the patient from bone marrow puncture