Abstract: A process for the preparation of a glucose-free glycosylated hemoglobin standard in which hemoglobin with a known content of glycosylated hemoglobin HbA.sub.Ia+b+c is converted to cyanmethemoglobin by means of a K.sub.3 (FeCN).sub.6 /KCN solution, stabilized with a sodium phosphate-cyanide buffer and preserved by lyophilizing at -40.degree. C. with a subsequent increase in temperature to -20.degree. C. under a high vacuum and stored at this temperature with the exclusion of light, whereupon the glucose-free glycosylated hemoglobin standard may be reconstituted by the addition of an aqueous medium.