This invention relates to a process for the preparation of glucosamine sulfate, glucosamine hydroiodide, glucosamine pyruvate, glucosamine phosphate or their mixtures with glucosamine hydrochloride, by electrodialysis. Starting from glucosamine hydrochloride, the exchange of the Cl.sup.- for an anion selected from the group consisting of SO.sub.4 .sup.-2, I.sup.-, CH.sub.3COCOO.sup.- and PO.sub.4.sup.-3 takes place during the process. The electrodialyser comprises a cathode, anode, and means of separation composed of anion exchange membranes, cation exchange membranes, bipolar membranes or by other suitable means of separation. This invention also relates to a glycosamine sulphate containing chlorides obtainable by the process, and its therapeutic use.